submodule/skia/src/gpu/ganesh/ops/DashOp.cpp

   1 /*
   2  * Copyright 2014 Google Inc.
   3  *
   4  * Use of this source code is governed by a BSD-style license that can be
   5  * found in the LICENSE file.
   6  */
   7
   8 #include "src/gpu/ganesh/ops/DashOp.h"
   9
  10 #include "include/gpu/GrRecordingContext.h"
  11 #include "src/core/SkMatrixPriv.h"
  12 #include "src/core/SkPointPriv.h"
  13 #include "src/gpu/BufferWriter.h"
  14 #include "src/gpu/KeyBuilder.h"
  15 #include "src/gpu/ganesh/GrAppliedClip.h"
  16 #include "src/gpu/ganesh/GrCaps.h"
  17 #include "src/gpu/ganesh/GrDefaultGeoProcFactory.h"
  18 #include "src/gpu/ganesh/GrGeometryProcessor.h"
  19 #include "src/gpu/ganesh/GrMemoryPool.h"
  20 #include "src/gpu/ganesh/GrOpFlushState.h"
  21 #include "src/gpu/ganesh/GrProcessor.h"
  22 #include "src/gpu/ganesh/GrProgramInfo.h"
  23 #include "src/gpu/ganesh/GrRecordingContextPriv.h"
  24 #include "src/gpu/ganesh/GrStyle.h"
  25 #include "src/gpu/ganesh/SkGr.h"
  26 #include "src/gpu/ganesh/geometry/GrQuad.h"
  27 #include "src/gpu/ganesh/glsl/GrGLSLFragmentShaderBuilder.h"
  28 #include "src/gpu/ganesh/glsl/GrGLSLProgramDataManager.h"
  29 #include "src/gpu/ganesh/glsl/GrGLSLUniformHandler.h"
  30 #include "src/gpu/ganesh/glsl/GrGLSLVarying.h"
  31 #include "src/gpu/ganesh/glsl/GrGLSLVertexGeoBuilder.h"
  32 #include "src/gpu/ganesh/ops/GrMeshDrawOp.h"
  33 #include "src/gpu/ganesh/ops/GrSimpleMeshDrawOpHelper.h"
  34
  35 using AAMode = skgpu::v1::DashOp::AAMode;
  36
  37 #if GR_TEST_UTILS
  38 static const int kAAModeCnt = static_cast<int>(skgpu::v1::DashOp::AAMode::kCoverageWithMSAA) + 1;
  39 #endif
  40
  41 namespace skgpu::v1::DashOp {
  42
  43 namespace {
  44
  45 void calc_dash_scaling(SkScalar* parallelScale, SkScalar* perpScale,
  46                        const SkMatrix& viewMatrix, const SkPoint pts[2]) {
  47     SkVector vecSrc = pts[1] - pts[0];
  48     if (pts[1] == pts[0]) {
  49         vecSrc.set(1.0, 0.0);
  50     }
  51     SkScalar magSrc = vecSrc.length();
  52     SkScalar invSrc = magSrc ? SkScalarInvert(magSrc) : 0;
  53     vecSrc.scale(invSrc);
  54
  55     SkVector vecSrcPerp;
  56     SkPointPriv::RotateCW(vecSrc, &vecSrcPerp);
  57     viewMatrix.mapVectors(&vecSrc, 1);
  58     viewMatrix.mapVectors(&vecSrcPerp, 1);
  59
  60     // parallelScale tells how much to scale along the line parallel to the dash line
  61     // perpScale tells how much to scale in the direction perpendicular to the dash line
  62     *parallelScale = vecSrc.length();
  63     *perpScale = vecSrcPerp.length();
  64 }
  65
  66 // calculates the rotation needed to aligned pts to the x axis with pts[0] < pts[1]
  67 // Stores the rotation matrix in rotMatrix, and the mapped points in ptsRot
  68 void align_to_x_axis(const SkPoint pts[2], SkMatrix* rotMatrix, SkPoint ptsRot[2] = nullptr) {
  69     SkVector vec = pts[1] - pts[0];
  70     if (pts[1] == pts[0]) {
  71         vec.set(1.0, 0.0);
  72     }
  73     SkScalar mag = vec.length();
  74     SkScalar inv = mag ? SkScalarInvert(mag) : 0;
  75
  76     vec.scale(inv);
  77     rotMatrix->setSinCos(-vec.fY, vec.fX, pts[0].fX, pts[0].fY);
  78     if (ptsRot) {
  79         rotMatrix->mapPoints(ptsRot, pts, 2);
  80         // correction for numerical issues if map doesn't make ptsRot exactly horizontal
  81         ptsRot[1].fY = pts[0].fY;
  82     }
  83 }
  84
  85 // Assumes phase < sum of all intervals
  86 SkScalar calc_start_adjustment(const SkScalar intervals[2], SkScalar phase) {
  87     SkASSERT(phase < intervals[0] + intervals[1]);
  88     if (phase >= intervals[0] && phase != 0) {
  89         SkScalar srcIntervalLen = intervals[0] + intervals[1];
  90         return srcIntervalLen - phase;
  91     }
  92     return 0;
  93 }
  94
  95 SkScalar calc_end_adjustment(const SkScalar intervals[2], const SkPoint pts[2],
  96                              SkScalar phase, SkScalar* endingInt) {
  97     if (pts[1].fX <= pts[0].fX) {
  98         return 0;
  99     }
 100     SkScalar srcIntervalLen = intervals[0] + intervals[1];
 101     SkScalar totalLen = pts[1].fX - pts[0].fX;
 102     SkScalar temp = totalLen / srcIntervalLen;
 103     SkScalar numFullIntervals = SkScalarFloorToScalar(temp);
 104     *endingInt = totalLen - numFullIntervals * srcIntervalLen + phase;
 105     temp = *endingInt / srcIntervalLen;
 106     *endingInt = *endingInt - SkScalarFloorToScalar(temp) * srcIntervalLen;
 107     if (0 == *endingInt) {
 108         *endingInt = srcIntervalLen;
 109     }
 110     if (*endingInt > intervals[0]) {
 111         return *endingInt - intervals[0];
 112     }
 113     return 0;
 114 }
 115
 116 enum DashCap {
 117     kRound_DashCap,
 118     kNonRound_DashCap,
 119 };
 120
 121 void setup_dashed_rect(const SkRect& rect,
 122                        VertexWriter& vertices,
 123                        const SkMatrix& matrix,
 124                        SkScalar offset,
 125                        SkScalar bloatX,
 126                        SkScalar len,
 127                        SkScalar startInterval,
 128                        SkScalar endInterval,
 129                        SkScalar strokeWidth,
 130                        SkScalar perpScale,
 131                        DashCap cap) {
 132     SkScalar intervalLength = startInterval + endInterval;
 133     // 'dashRect' gets interpolated over the rendered 'rect'. For y we want the perpendicular signed
 134     // distance from the stroke center line in device space. 'perpScale' is the scale factor applied
 135     // to the y dimension of 'rect' isolated from 'matrix'.
 136     SkScalar halfDevRectHeight = rect.height() * perpScale / 2.f;
 137     SkRect dashRect = { offset       - bloatX, -halfDevRectHeight,
 138                         offset + len + bloatX,  halfDevRectHeight };
 139
 140     if (kRound_DashCap == cap) {
 141         SkScalar radius = SkScalarHalf(strokeWidth) - 0.5f;
 142         SkScalar centerX = SkScalarHalf(endInterval);
 143
 144         vertices.writeQuad(GrQuad::MakeFromRect(rect, matrix),
 145                            VertexWriter::TriStripFromRect(dashRect),
 146                            intervalLength,
 147                            radius,
 148                            centerX);
 149     } else {
 150         SkASSERT(kNonRound_DashCap == cap);
 151         SkScalar halfOffLen = SkScalarHalf(endInterval);
 152         SkScalar halfStroke = SkScalarHalf(strokeWidth);
 153         SkRect rectParam;
 154         rectParam.setLTRB(halfOffLen                 + 0.5f, -halfStroke + 0.5f,
 155                           halfOffLen + startInterval - 0.5f,  halfStroke - 0.5f);
 156
 157         vertices.writeQuad(GrQuad::MakeFromRect(rect, matrix),
 158                            VertexWriter::TriStripFromRect(dashRect),
 159                            intervalLength,
 160                            rectParam);
 161     }
 162 }
 163
 164 /**
 165  * An GrGeometryProcessor that renders a dashed line.
 166  * This GrGeometryProcessor is meant for dashed lines that only have a single on/off interval pair.
 167  * Bounding geometry is rendered and the effect computes coverage based on the fragment's
 168  * position relative to the dashed line.
 169  */
 170 GrGeometryProcessor* make_dash_gp(SkArenaAlloc* arena,
 171                                   const SkPMColor4f&,
 172                                   AAMode aaMode,
 173                                   DashCap cap,
 174                                   const SkMatrix& localMatrix,
 175                                   bool usesLocalCoords);
 176
 177 class DashOpImpl final : public GrMeshDrawOp {
 178 public:
 179     DEFINE_OP_CLASS_ID
 180
 181     struct LineData {
 182         SkMatrix fViewMatrix;
 183         SkMatrix fSrcRotInv;
 184         SkPoint fPtsRot[2];
 185         SkScalar fSrcStrokeWidth;
 186         SkScalar fPhase;
 187         SkScalar fIntervals[2];
 188         SkScalar fParallelScale;
 189         SkScalar fPerpendicularScale;
 190     };
 191
 192     static GrOp::Owner Make(GrRecordingContext* context,
 193                             GrPaint&& paint,
 194                             const LineData& geometry,
 195                             SkPaint::Cap cap,
 196                             AAMode aaMode, bool fullDash,
 197                             const GrUserStencilSettings* stencilSettings) {
 198         return GrOp::Make<DashOpImpl>(context, std::move(paint), geometry, cap,
 199                                       aaMode, fullDash, stencilSettings);
 200     }
 201
 202     const char* name() const override { return "DashOp"; }
 203
 204     void visitProxies(const GrVisitProxyFunc& func) const override {
 205         if (fProgramInfo) {
 206             fProgramInfo->visitFPProxies(func);
 207         } else {
 208             fProcessorSet.visitProxies(func);
 209         }
 210     }
 211
 212     FixedFunctionFlags fixedFunctionFlags() const override {
 213         FixedFunctionFlags flags = FixedFunctionFlags::kNone;
 214         if (AAMode::kCoverageWithMSAA == fAAMode) {
 215             flags |= FixedFunctionFlags::kUsesHWAA;
 216         }
 217         if (fStencilSettings != &GrUserStencilSettings::kUnused) {
 218             flags |= FixedFunctionFlags::kUsesStencil;
 219         }
 220         return flags;
 221     }
 222
 223     GrProcessorSet::Analysis finalize(const GrCaps& caps, const GrAppliedClip* clip,
 224                                       GrClampType clampType) override {
 225         GrProcessorAnalysisCoverage coverage = GrProcessorAnalysisCoverage::kSingleChannel;
 226         auto analysis = fProcessorSet.finalize(fColor, coverage, clip, fStencilSettings, caps,
 227                                                clampType, &fColor);
 228         fUsesLocalCoords = analysis.usesLocalCoords();
 229         return analysis;
 230     }
 231
 232 private:
 233     friend class GrOp; // for ctor
 234
 235     DashOpImpl(GrPaint&& paint, const LineData& geometry, SkPaint::Cap cap, AAMode aaMode,
 236                bool fullDash, const GrUserStencilSettings* stencilSettings)
 237             : INHERITED(ClassID())
 238             , fColor(paint.getColor4f())
 239             , fFullDash(fullDash)
 240             , fCap(cap)
 241             , fAAMode(aaMode)
 242             , fProcessorSet(std::move(paint))
 243             , fStencilSettings(stencilSettings) {
 244         fLines.push_back(geometry);
 245
 246         // compute bounds
 247         SkScalar halfStrokeWidth = 0.5f * geometry.fSrcStrokeWidth;
 248         SkScalar xBloat = SkPaint::kButt_Cap == cap ? 0 : halfStrokeWidth;
 249         SkRect bounds;
 250         bounds.set(geometry.fPtsRot[0], geometry.fPtsRot[1]);
 251         bounds.outset(xBloat, halfStrokeWidth);
 252
 253         // Note, we actually create the combined matrix here, and save the work
 254         SkMatrix& combinedMatrix = fLines[0].fSrcRotInv;
 255         combinedMatrix.postConcat(geometry.fViewMatrix);
 256
 257         IsHairline zeroArea = geometry.fSrcStrokeWidth ? IsHairline::kNo : IsHairline::kYes;
 258         HasAABloat aaBloat = (aaMode == AAMode::kNone) ? HasAABloat::kNo : HasAABloat::kYes;
 259         this->setTransformedBounds(bounds, combinedMatrix, aaBloat, zeroArea);
 260     }
 261
 262     struct DashDraw {
 263         DashDraw(const LineData& geo) {
 264             memcpy(fPtsRot, geo.fPtsRot, sizeof(geo.fPtsRot));
 265             memcpy(fIntervals, geo.fIntervals, sizeof(geo.fIntervals));
 266             fPhase = geo.fPhase;
 267         }
 268         SkPoint fPtsRot[2];
 269         SkScalar fIntervals[2];
 270         SkScalar fPhase;
 271         SkScalar fStartOffset;
 272         SkScalar fStrokeWidth;
 273         SkScalar fLineLength;
 274         SkScalar fDevBloatX;
 275         SkScalar fPerpendicularScale;
 276         bool fLineDone;
 277         bool fHasStartRect;
 278         bool fHasEndRect;
 279     };
 280
 281     GrProgramInfo* programInfo() override { return fProgramInfo; }
 282
 283     void onCreateProgramInfo(const GrCaps* caps,
 284                              SkArenaAlloc* arena,
 285                              const GrSurfaceProxyView& writeView,
 286                              bool usesMSAASurface,
 287                              GrAppliedClip&& appliedClip,
 288                              const GrDstProxyView& dstProxyView,
 289                              GrXferBarrierFlags renderPassXferBarriers,
 290                              GrLoadOp colorLoadOp) override {
 291
 292         DashCap capType = (this->cap() == SkPaint::kRound_Cap) ? kRound_DashCap : kNonRound_DashCap;
 293
 294         GrGeometryProcessor* gp;
 295         if (this->fullDash()) {
 296             gp = make_dash_gp(arena, this->color(), this->aaMode(), capType,
 297                               this->viewMatrix(), fUsesLocalCoords);
 298         } else {
 299             // Set up the vertex data for the line and start/end dashes
 300             using namespace GrDefaultGeoProcFactory;
 301             Color color(this->color());
 302             LocalCoords::Type localCoordsType =
 303                     fUsesLocalCoords ? LocalCoords::kUsePosition_Type : LocalCoords::kUnused_Type;
 304             gp = MakeForDeviceSpace(arena,
 305                                     color,
 306                                     Coverage::kSolid_Type,
 307                                     localCoordsType,
 308                                     this->viewMatrix());
 309         }
 310
 311         if (!gp) {
 312             SkDebugf("Could not create GrGeometryProcessor\n");
 313             return;
 314         }
 315
 316         fProgramInfo = GrSimpleMeshDrawOpHelper::CreateProgramInfo(caps,
 317                                                                    arena,
 318                                                                    writeView,
 319                                                                    usesMSAASurface,
 320                                                                    std::move(appliedClip),
 321                                                                    dstProxyView,
 322                                                                    gp,
 323                                                                    std::move(fProcessorSet),
 324                                                                    GrPrimitiveType::kTriangles,
 325                                                                    renderPassXferBarriers,
 326                                                                    colorLoadOp,
 327                                                                    GrPipeline::InputFlags::kNone,
 328                                                                    fStencilSettings);
 329     }
 330
 331     void onPrepareDraws(GrMeshDrawTarget* target) override {
 332         int instanceCount = fLines.count();
 333         SkPaint::Cap cap = this->cap();
 334         DashCap capType = (SkPaint::kRound_Cap == cap) ? kRound_DashCap : kNonRound_DashCap;
 335
 336         if (!fProgramInfo) {
 337             this->createProgramInfo(target);
 338             if (!fProgramInfo) {
 339                 return;
 340             }
 341         }
 342
 343         // useAA here means Edge AA or MSAA
 344         bool useAA = this->aaMode() != AAMode::kNone;
 345         bool fullDash = this->fullDash();
 346
 347         // We do two passes over all of the dashes.  First we setup the start, end, and bounds,
 348         // rectangles.  We preserve all of this work in the rects / draws arrays below.  Then we
 349         // iterate again over these decomposed dashes to generate vertices
 350         static const int kNumStackDashes = 128;
 351         SkSTArray<kNumStackDashes, SkRect, true> rects;
 352         SkSTArray<kNumStackDashes, DashDraw, true> draws;
 353
 354         int totalRectCount = 0;
 355         int rectOffset = 0;
 356         rects.push_back_n(3 * instanceCount);
 357         for (int i = 0; i < instanceCount; i++) {
 358             const LineData& args = fLines[i];
 359
 360             DashDraw& draw = draws.push_back(args);
 361
 362             bool hasCap = SkPaint::kButt_Cap != cap;
 363
 364             SkScalar halfSrcStroke = args.fSrcStrokeWidth * 0.5f;
 365             if (halfSrcStroke == 0.0f || this->aaMode() != AAMode::kCoverageWithMSAA) {
 366                 // In the non-MSAA case, we always want to at least stroke out half a pixel on each
 367                 // side in device space. 0.5f / fPerpendicularScale gives us this min in src space.
 368                 // This is also necessary when the stroke width is zero, to allow hairlines to draw.
 369                 halfSrcStroke = std::max(halfSrcStroke, 0.5f / args.fPerpendicularScale);
 370             }
 371
 372             SkScalar strokeAdj = hasCap ? halfSrcStroke : 0.0f;
 373             SkScalar startAdj = 0;
 374
 375             bool lineDone = false;
 376
 377             // Too simplify the algorithm, we always push back rects for start and end rect.
 378             // Otherwise we'd have to track start / end rects for each individual geometry
 379             SkRect& bounds = rects[rectOffset++];
 380             SkRect& startRect = rects[rectOffset++];
 381             SkRect& endRect = rects[rectOffset++];
 382
 383             bool hasStartRect = false;
 384             // If we are using AA, check to see if we are drawing a partial dash at the start. If so
 385             // draw it separately here and adjust our start point accordingly
 386             if (useAA) {
 387                 if (draw.fPhase > 0 && draw.fPhase < draw.fIntervals[0]) {
 388                     SkPoint startPts[2];
 389                     startPts[0] = draw.fPtsRot[0];
 390                     startPts[1].fY = startPts[0].fY;
 391                     startPts[1].fX = std::min(startPts[0].fX + draw.fIntervals[0] - draw.fPhase,
 392                                               draw.fPtsRot[1].fX);
 393                     startRect.setBounds(startPts, 2);
 394                     startRect.outset(strokeAdj, halfSrcStroke);
 395
 396                     hasStartRect = true;
 397                     startAdj = draw.fIntervals[0] + draw.fIntervals[1] - draw.fPhase;
 398                 }
 399             }
 400
 401             // adjustments for start and end of bounding rect so we only draw dash intervals
 402             // contained in the original line segment.
 403             startAdj += calc_start_adjustment(draw.fIntervals, draw.fPhase);
 404             if (startAdj != 0) {
 405                 draw.fPtsRot[0].fX += startAdj;
 406                 draw.fPhase = 0;
 407             }
 408             SkScalar endingInterval = 0;
 409             SkScalar endAdj = calc_end_adjustment(draw.fIntervals, draw.fPtsRot, draw.fPhase,
 410                                                   &endingInterval);
 411             draw.fPtsRot[1].fX -= endAdj;
 412             if (draw.fPtsRot[0].fX >= draw.fPtsRot[1].fX) {
 413                 lineDone = true;
 414             }
 415
 416             bool hasEndRect = false;
 417             // If we are using AA, check to see if we are drawing a partial dash at then end. If so
 418             // draw it separately here and adjust our end point accordingly
 419             if (useAA && !lineDone) {
 420                 // If we adjusted the end then we will not be drawing a partial dash at the end.
 421                 // If we didn't adjust the end point then we just need to make sure the ending
 422                 // dash isn't a full dash
 423                 if (0 == endAdj && endingInterval != draw.fIntervals[0]) {
 424                     SkPoint endPts[2];
 425                     endPts[1] = draw.fPtsRot[1];
 426                     endPts[0].fY = endPts[1].fY;
 427                     endPts[0].fX = endPts[1].fX - endingInterval;
 428
 429                     endRect.setBounds(endPts, 2);
 430                     endRect.outset(strokeAdj, halfSrcStroke);
 431
 432                     hasEndRect = true;
 433                     endAdj = endingInterval + draw.fIntervals[1];
 434
 435                     draw.fPtsRot[1].fX -= endAdj;
 436                     if (draw.fPtsRot[0].fX >= draw.fPtsRot[1].fX) {
 437                         lineDone = true;
 438                     }
 439                 }
 440             }
 441
 442             if (draw.fPtsRot[0].fX == draw.fPtsRot[1].fX &&
 443                 (0 != endAdj || 0 == startAdj) &&
 444                 hasCap) {
 445                 // At this point the fPtsRot[0]/[1] represent the start and end of the inner rect of
 446                 // dashes that we want to draw. The only way they can be equal is if the on interval
 447                 // is zero (or an edge case if the end of line ends at a full off interval, but this
 448                 // is handled as well). Thus if the on interval is zero then we need to draw a cap
 449                 // at this position if the stroke has caps. The spec says we only draw this point if
 450                 // point lies between [start of line, end of line). Thus we check if we are at the
 451                 // end (but not the start), and if so we don't draw the cap.
 452                 lineDone = false;
 453             }
 454
 455             if (startAdj != 0) {
 456                 draw.fPhase = 0;
 457             }
 458
 459             // Change the dashing info from src space into device space
 460             SkScalar* devIntervals = draw.fIntervals;
 461             devIntervals[0] = draw.fIntervals[0] * args.fParallelScale;
 462             devIntervals[1] = draw.fIntervals[1] * args.fParallelScale;
 463             SkScalar devPhase = draw.fPhase * args.fParallelScale;
 464             SkScalar strokeWidth = args.fSrcStrokeWidth * args.fPerpendicularScale;
 465
 466             if ((strokeWidth < 1.f && !useAA) || 0.f == strokeWidth) {
 467                 strokeWidth = 1.f;
 468             }
 469
 470             SkScalar halfDevStroke = strokeWidth * 0.5f;
 471
 472             if (SkPaint::kSquare_Cap == cap) {
 473                 // add cap to on interval and remove from off interval
 474                 devIntervals[0] += strokeWidth;
 475                 devIntervals[1] -= strokeWidth;
 476             }
 477             SkScalar startOffset = devIntervals[1] * 0.5f + devPhase;
 478
 479             SkScalar devBloatX = 0.0f;
 480             SkScalar devBloatY = 0.0f;
 481             switch (this->aaMode()) {
 482                 case AAMode::kNone:
 483                     break;
 484                 case AAMode::kCoverage:
 485                     // For EdgeAA, we bloat in X & Y for both square and round caps.
 486                     devBloatX = 0.5f;
 487                     devBloatY = 0.5f;
 488                     break;
 489                 case AAMode::kCoverageWithMSAA:
 490                     // For MSAA, we only bloat in Y for round caps.
 491                     devBloatY = (cap == SkPaint::kRound_Cap) ? 0.5f : 0.0f;
 492                     break;
 493             }
 494
 495             SkScalar bloatX = devBloatX / args.fParallelScale;
 496             SkScalar bloatY = devBloatY / args.fPerpendicularScale;
 497
 498             if (devIntervals[1] <= 0.f && useAA) {
 499                 // Case when we end up drawing a solid AA rect
 500                 // Reset the start rect to draw this single solid rect
 501                 // but it requires to upload a new intervals uniform so we can mimic
 502                 // one giant dash
 503                 draw.fPtsRot[0].fX -= hasStartRect ? startAdj : 0;
 504                 draw.fPtsRot[1].fX += hasEndRect ? endAdj : 0;
 505                 startRect.setBounds(draw.fPtsRot, 2);
 506                 startRect.outset(strokeAdj, halfSrcStroke);
 507                 hasStartRect = true;
 508                 hasEndRect = false;
 509                 lineDone = true;
 510
 511                 SkPoint devicePts[2];
 512                 args.fSrcRotInv.mapPoints(devicePts, draw.fPtsRot, 2);
 513                 SkScalar lineLength = SkPoint::Distance(devicePts[0], devicePts[1]);
 514                 if (hasCap) {
 515                     lineLength += 2.f * halfDevStroke;
 516                 }
 517                 devIntervals[0] = lineLength;
 518             }
 519
 520             totalRectCount += !lineDone ? 1 : 0;
 521             totalRectCount += hasStartRect ? 1 : 0;
 522             totalRectCount += hasEndRect ? 1 : 0;
 523
 524             if (SkPaint::kRound_Cap == cap && 0 != args.fSrcStrokeWidth) {
 525                 // need to adjust this for round caps to correctly set the dashPos attrib on
 526                 // vertices
 527                 startOffset -= halfDevStroke;
 528             }
 529
 530             if (!lineDone) {
 531                 SkPoint devicePts[2];
 532                 args.fSrcRotInv.mapPoints(devicePts, draw.fPtsRot, 2);
 533                 draw.fLineLength = SkPoint::Distance(devicePts[0], devicePts[1]);
 534                 if (hasCap) {
 535                     draw.fLineLength += 2.f * halfDevStroke;
 536                 }
 537
 538                 bounds.setLTRB(draw.fPtsRot[0].fX, draw.fPtsRot[0].fY,
 539                                draw.fPtsRot[1].fX, draw.fPtsRot[1].fY);
 540                 bounds.outset(bloatX + strokeAdj, bloatY + halfSrcStroke);
 541             }
 542
 543             if (hasStartRect) {
 544                 SkASSERT(useAA);  // so that we know bloatX and bloatY have been set
 545                 startRect.outset(bloatX, bloatY);
 546             }
 547
 548             if (hasEndRect) {
 549                 SkASSERT(useAA);  // so that we know bloatX and bloatY have been set
 550                 endRect.outset(bloatX, bloatY);
 551             }
 552
 553             draw.fStartOffset = startOffset;
 554             draw.fDevBloatX = devBloatX;
 555             draw.fPerpendicularScale = args.fPerpendicularScale;
 556             draw.fStrokeWidth = strokeWidth;
 557             draw.fHasStartRect = hasStartRect;
 558             draw.fLineDone = lineDone;
 559             draw.fHasEndRect = hasEndRect;
 560         }
 561
 562         if (!totalRectCount) {
 563             return;
 564         }
 565
 566         QuadHelper helper(target, fProgramInfo->geomProc().vertexStride(), totalRectCount);
 567         VertexWriter vertices{ helper.vertices() };
 568         if (!vertices) {
 569             return;
 570         }
 571
 572         int rectIndex = 0;
 573         for (int i = 0; i < instanceCount; i++) {
 574             const LineData& geom = fLines[i];
 575
 576             if (!draws[i].fLineDone) {
 577                 if (fullDash) {
 578                     setup_dashed_rect(rects[rectIndex], vertices, geom.fSrcRotInv,
 579                                       draws[i].fStartOffset, draws[i].fDevBloatX,
 580                                       draws[i].fLineLength, draws[i].fIntervals[0],
 581                                       draws[i].fIntervals[1], draws[i].fStrokeWidth,
 582                                       draws[i].fPerpendicularScale,
 583                                       capType);
 584                 } else {
 585                     vertices.writeQuad(GrQuad::MakeFromRect(rects[rectIndex], geom.fSrcRotInv));
 586                 }
 587             }
 588             rectIndex++;
 589
 590             if (draws[i].fHasStartRect) {
 591                 if (fullDash) {
 592                     setup_dashed_rect(rects[rectIndex], vertices, geom.fSrcRotInv,
 593                                       draws[i].fStartOffset, draws[i].fDevBloatX,
 594                                       draws[i].fIntervals[0], draws[i].fIntervals[0],
 595                                       draws[i].fIntervals[1], draws[i].fStrokeWidth,
 596                                       draws[i].fPerpendicularScale, capType);
 597                 } else {
 598                     vertices.writeQuad(GrQuad::MakeFromRect(rects[rectIndex], geom.fSrcRotInv));
 599                 }
 600             }
 601             rectIndex++;
 602
 603             if (draws[i].fHasEndRect) {
 604                 if (fullDash) {
 605                     setup_dashed_rect(rects[rectIndex], vertices, geom.fSrcRotInv,
 606                                       draws[i].fStartOffset, draws[i].fDevBloatX,
 607                                       draws[i].fIntervals[0], draws[i].fIntervals[0],
 608                                       draws[i].fIntervals[1], draws[i].fStrokeWidth,
 609                                       draws[i].fPerpendicularScale, capType);
 610                 } else {
 611                     vertices.writeQuad(GrQuad::MakeFromRect(rects[rectIndex], geom.fSrcRotInv));
 612                 }
 613             }
 614             rectIndex++;
 615         }
 616
 617         fMesh = helper.mesh();
 618     }
 619
 620     void onExecute(GrOpFlushState* flushState, const SkRect& chainBounds) override {
 621         if (!fProgramInfo || !fMesh) {
 622             return;
 623         }
 624
 625         flushState->bindPipelineAndScissorClip(*fProgramInfo, chainBounds);
 626         flushState->bindTextures(fProgramInfo->geomProc(), nullptr, fProgramInfo->pipeline());
 627         flushState->drawMesh(*fMesh);
 628     }
 629
 630     CombineResult onCombineIfPossible(GrOp* t, SkArenaAlloc*, const GrCaps& caps) override {
 631         auto that = t->cast<DashOpImpl>();
 632         if (fProcessorSet != that->fProcessorSet) {
 633             return CombineResult::kCannotCombine;
 634         }
 635
 636         if (this->aaMode() != that->aaMode()) {
 637             return CombineResult::kCannotCombine;
 638         }
 639
 640         if (this->fullDash() != that->fullDash()) {
 641             return CombineResult::kCannotCombine;
 642         }
 643
 644         if (this->cap() != that->cap()) {
 645             return CombineResult::kCannotCombine;
 646         }
 647
 648         // TODO vertex color
 649         if (this->color() != that->color()) {
 650             return CombineResult::kCannotCombine;
 651         }
 652
 653         if (fUsesLocalCoords && !SkMatrixPriv::CheapEqual(this->viewMatrix(), that->viewMatrix())) {
 654             return CombineResult::kCannotCombine;
 655         }
 656
 657         fLines.push_back_n(that->fLines.count(), that->fLines.begin());
 658         return CombineResult::kMerged;
 659     }
 660
 661 #if GR_TEST_UTILS
 662     SkString onDumpInfo() const override {
 663         SkString string;
 664         for (const auto& geo : fLines) {
 665             string.appendf("Pt0: [%.2f, %.2f], Pt1: [%.2f, %.2f], Width: %.2f, Ival0: %.2f, "
 666                            "Ival1 : %.2f, Phase: %.2f\n",
 667                            geo.fPtsRot[0].fX, geo.fPtsRot[0].fY,
 668                            geo.fPtsRot[1].fX, geo.fPtsRot[1].fY,
 669                            geo.fSrcStrokeWidth,
 670                            geo.fIntervals[0],
 671                            geo.fIntervals[1],
 672                            geo.fPhase);
 673         }
 674         string += fProcessorSet.dumpProcessors();
 675         return string;
 676     }
 677 #endif
 678
 679     const SkPMColor4f& color() const { return fColor; }
 680     const SkMatrix& viewMatrix() const { return fLines[0].fViewMatrix; }
 681     AAMode aaMode() const { return fAAMode; }
 682     bool fullDash() const { return fFullDash; }
 683     SkPaint::Cap cap() const { return fCap; }
 684
 685     SkSTArray<1, LineData, true> fLines;
 686     SkPMColor4f fColor;
 687     bool fUsesLocalCoords : 1;
 688     bool fFullDash : 1;
 689     // We use 3 bits for this 3-value enum because MSVS makes the underlying types signed.
 690     SkPaint::Cap fCap : 3;
 691     AAMode fAAMode;
 692     GrProcessorSet fProcessorSet;
 693     const GrUserStencilSettings* fStencilSettings;
 694
 695     GrSimpleMesh*  fMesh = nullptr;
 696     GrProgramInfo* fProgramInfo = nullptr;
 697
 698     using INHERITED = GrMeshDrawOp;
 699 };
 700
 701 /*
 702  * This effect will draw a dotted line (defined as a dashed lined with round caps and no on
 703  * interval). The radius of the dots is given by the strokeWidth and the spacing by the DashInfo.
 704  * Both of the previous two parameters are in device space. This effect also requires the setting of
 705  * a float2 vertex attribute for the the four corners of the bounding rect. This attribute is the
 706  * "dash position" of each vertex. In other words it is the vertex coords (in device space) if we
 707  * transform the line to be horizontal, with the start of line at the origin then shifted to the
 708  * right by half the off interval. The line then goes in the positive x direction.
 709  */
 710 class DashingCircleEffect : public GrGeometryProcessor {
 711 public:
 712     typedef SkPathEffect::DashInfo DashInfo;
 713
 714     static GrGeometryProcessor* Make(SkArenaAlloc* arena,
 715                                      const SkPMColor4f&,
 716                                      AAMode aaMode,
 717                                      const SkMatrix& localMatrix,
 718                                      bool usesLocalCoords);
 719
 720     const char* name() const override { return "DashingCircleEffect"; }
 721
 722     void addToKey(const GrShaderCaps&, KeyBuilder*) const override;
 723
 724     std::unique_ptr<ProgramImpl> makeProgramImpl(const GrShaderCaps&) const override;
 725
 726 private:
 727     class Impl;
 728
 729     DashingCircleEffect(const SkPMColor4f&, AAMode aaMode, const SkMatrix& localMatrix,
 730                         bool usesLocalCoords);
 731
 732     SkPMColor4f fColor;
 733     SkMatrix    fLocalMatrix;
 734     bool        fUsesLocalCoords;
 735     AAMode      fAAMode;
 736
 737     Attribute   fInPosition;
 738     Attribute   fInDashParams;
 739     Attribute   fInCircleParams;
 740
 741     GR_DECLARE_GEOMETRY_PROCESSOR_TEST
 742
 743     using INHERITED = GrGeometryProcessor;
 744 };
 745
 746 //////////////////////////////////////////////////////////////////////////////
 747
 748 class DashingCircleEffect::Impl : public ProgramImpl {
 749 public:
 750     void setData(const GrGLSLProgramDataManager&,
 751                  const GrShaderCaps&,
 752                  const GrGeometryProcessor&) override;
 753
 754 private:
 755     void onEmitCode(EmitArgs&, GrGPArgs*) override;
 756
 757     SkMatrix    fLocalMatrix         = SkMatrix::InvalidMatrix();
 758     SkPMColor4f fColor               = SK_PMColor4fILLEGAL;
 759     float       fPrevRadius          = SK_FloatNaN;
 760     float       fPrevCenterX         = SK_FloatNaN;
 761     float       fPrevIntervalLength  = SK_FloatNaN;
 762
 763     UniformHandle fParamUniform;
 764     UniformHandle fColorUniform;
 765     UniformHandle fLocalMatrixUniform;
 766 };
 767
 768 void DashingCircleEffect::Impl::onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) {
 769     const DashingCircleEffect& dce = args.fGeomProc.cast<DashingCircleEffect>();
 770     GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
 771     GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
 772     GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
 773
 774     // emit attributes
 775     varyingHandler->emitAttributes(dce);
 776
 777     // XY are dashPos, Z is dashInterval
 778     GrGLSLVarying dashParams(SkSLType::kHalf3);
 779     varyingHandler->addVarying("DashParam", &dashParams);
 780     vertBuilder->codeAppendf("%s = %s;", dashParams.vsOut(), dce.fInDashParams.name());
 781
 782     // x refers to circle radius - 0.5, y refers to cicle's center x coord
 783     GrGLSLVarying circleParams(SkSLType::kHalf2);
 784     varyingHandler->addVarying("CircleParams", &circleParams);
 785     vertBuilder->codeAppendf("%s = %s;", circleParams.vsOut(), dce.fInCircleParams.name());
 786
 787     GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
 788     // Setup pass through color
 789     fragBuilder->codeAppendf("half4 %s;", args.fOutputColor);
 790     this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor, &fColorUniform);
 791
 792     // Setup position
 793     WriteOutputPosition(vertBuilder, gpArgs, dce.fInPosition.name());
 794     if (dce.fUsesLocalCoords) {
 795         WriteLocalCoord(vertBuilder,
 796                         uniformHandler,
 797                         *args.fShaderCaps,
 798                         gpArgs,
 799                         dce.fInPosition.asShaderVar(),
 800                         dce.fLocalMatrix,
 801                         &fLocalMatrixUniform);
 802     }
 803
 804     // transforms all points so that we can compare them to our test circle
 805     fragBuilder->codeAppendf("half xShifted = half(%s.x - floor(%s.x / %s.z) * %s.z);",
 806                              dashParams.fsIn(), dashParams.fsIn(), dashParams.fsIn(),
 807                              dashParams.fsIn());
 808     fragBuilder->codeAppendf("half2 fragPosShifted = half2(xShifted, half(%s.y));",
 809                              dashParams.fsIn());
 810     fragBuilder->codeAppendf("half2 center = half2(%s.y, 0.0);", circleParams.fsIn());
 811     fragBuilder->codeAppend("half dist = length(center - fragPosShifted);");
 812     if (dce.fAAMode != AAMode::kNone) {
 813         fragBuilder->codeAppendf("half diff = dist - %s.x;", circleParams.fsIn());
 814         fragBuilder->codeAppend("diff = 1.0 - diff;");
 815         fragBuilder->codeAppend("half alpha = saturate(diff);");
 816     } else {
 817         fragBuilder->codeAppendf("half alpha = 1.0;");
 818         fragBuilder->codeAppendf("alpha *=  dist < %s.x + 0.5 ? 1.0 : 0.0;", circleParams.fsIn());
 819     }
 820     fragBuilder->codeAppendf("half4 %s = half4(alpha);", args.fOutputCoverage);
 821 }
 822
 823 void DashingCircleEffect::Impl::setData(const GrGLSLProgramDataManager& pdman,
 824                                         const GrShaderCaps& shaderCaps,
 825                                         const GrGeometryProcessor& geomProc) {
 826     const DashingCircleEffect& dce = geomProc.cast<DashingCircleEffect>();
 827     if (dce.fColor != fColor) {
 828         pdman.set4fv(fColorUniform, 1, dce.fColor.vec());
 829         fColor = dce.fColor;
 830     }
 831     SetTransform(pdman, shaderCaps, fLocalMatrixUniform, dce.fLocalMatrix, &fLocalMatrix);
 832 }
 833
 834 //////////////////////////////////////////////////////////////////////////////
 835
 836 GrGeometryProcessor* DashingCircleEffect::Make(SkArenaAlloc* arena,
 837                                                const SkPMColor4f& color,
 838                                                AAMode aaMode,
 839                                                const SkMatrix& localMatrix,
 840                                                bool usesLocalCoords) {
 841     return arena->make([&](void* ptr) {
 842         return new (ptr) DashingCircleEffect(color, aaMode, localMatrix, usesLocalCoords);
 843     });
 844 }
 845
 846 void DashingCircleEffect::addToKey(const GrShaderCaps& caps, KeyBuilder* b) const {
 847     uint32_t key = 0;
 848     key |= fUsesLocalCoords ? 0x1 : 0x0;
 849     key |= static_cast<uint32_t>(fAAMode) << 1;
 850     key |= ProgramImpl::ComputeMatrixKey(caps, fLocalMatrix) << 3;
 851     b->add32(key);
 852 }
 853
 854 std::unique_ptr<GrGeometryProcessor::ProgramImpl> DashingCircleEffect::makeProgramImpl(
 855         const GrShaderCaps&) const {
 856     return std::make_unique<Impl>();
 857 }
 858
 859 DashingCircleEffect::DashingCircleEffect(const SkPMColor4f& color,
 860                                          AAMode aaMode,
 861                                          const SkMatrix& localMatrix,
 862                                          bool usesLocalCoords)
 863         : INHERITED(kDashingCircleEffect_ClassID)
 864         , fColor(color)
 865         , fLocalMatrix(localMatrix)
 866         , fUsesLocalCoords(usesLocalCoords)
 867         , fAAMode(aaMode) {
 868     fInPosition = {"inPosition", kFloat2_GrVertexAttribType, SkSLType::kFloat2};
 869     fInDashParams = {"inDashParams", kFloat3_GrVertexAttribType, SkSLType::kHalf3};
 870     fInCircleParams = {"inCircleParams", kFloat2_GrVertexAttribType, SkSLType::kHalf2};
 871     this->setVertexAttributesWithImplicitOffsets(&fInPosition, 3);
 872 }
 873
 874 GR_DEFINE_GEOMETRY_PROCESSOR_TEST(DashingCircleEffect);
 875
 876 #if GR_TEST_UTILS
 877 GrGeometryProcessor* DashingCircleEffect::TestCreate(GrProcessorTestData* d) {
 878     AAMode aaMode = static_cast<AAMode>(d->fRandom->nextULessThan(kAAModeCnt));
 879     GrColor color = GrTest::RandomColor(d->fRandom);
 880     SkMatrix matrix = GrTest::TestMatrix(d->fRandom);
 881     return DashingCircleEffect::Make(d->allocator(),
 882                                      SkPMColor4f::FromBytes_RGBA(color),
 883                                      aaMode,
 884                                      matrix,
 885                                      d->fRandom->nextBool());
 886 }
 887 #endif
 888
 889 //////////////////////////////////////////////////////////////////////////////
 890
 891 /*
 892  * This effect will draw a dashed line. The width of the dash is given by the strokeWidth and the
 893  * length and spacing by the DashInfo. Both of the previous two parameters are in device space.
 894  * This effect also requires the setting of a float2 vertex attribute for the the four corners of the
 895  * bounding rect. This attribute is the "dash position" of each vertex. In other words it is the
 896  * vertex coords (in device space) if we transform the line to be horizontal, with the start of
 897  * line at the origin then shifted to the right by half the off interval. The line then goes in the
 898  * positive x direction.
 899  */
 900 class DashingLineEffect : public GrGeometryProcessor {
 901 public:
 902     typedef SkPathEffect::DashInfo DashInfo;
 903
 904     static GrGeometryProcessor* Make(SkArenaAlloc* arena,
 905                                      const SkPMColor4f&,
 906                                      AAMode aaMode,
 907                                      const SkMatrix& localMatrix,
 908                                      bool usesLocalCoords);
 909
 910     const char* name() const override { return "DashingEffect"; }
 911
 912     bool usesLocalCoords() const { return fUsesLocalCoords; }
 913
 914     void addToKey(const GrShaderCaps&, KeyBuilder*) const override;
 915
 916     std::unique_ptr<ProgramImpl> makeProgramImpl(const GrShaderCaps&) const override;
 917
 918 private:
 919     class Impl;
 920
 921     DashingLineEffect(const SkPMColor4f&, AAMode aaMode, const SkMatrix& localMatrix,
 922                       bool usesLocalCoords);
 923
 924     SkPMColor4f fColor;
 925     SkMatrix    fLocalMatrix;
 926     bool        fUsesLocalCoords;
 927     AAMode      fAAMode;
 928
 929     Attribute   fInPosition;
 930     Attribute   fInDashParams;
 931     Attribute   fInRect;
 932
 933     GR_DECLARE_GEOMETRY_PROCESSOR_TEST
 934
 935     using INHERITED = GrGeometryProcessor;
 936 };
 937
 938 //////////////////////////////////////////////////////////////////////////////
 939
 940 class DashingLineEffect::Impl : public ProgramImpl {
 941 public:
 942     void setData(const GrGLSLProgramDataManager&,
 943                  const GrShaderCaps&,
 944                  const GrGeometryProcessor&) override;
 945
 946 private:
 947     void onEmitCode(EmitArgs&, GrGPArgs*) override;
 948
 949     SkPMColor4f fColor       = SK_PMColor4fILLEGAL;
 950     SkMatrix    fLocalMatrix = SkMatrix::InvalidMatrix();
 951
 952     UniformHandle fLocalMatrixUniform;
 953     UniformHandle fColorUniform;
 954 };
 955
 956 void DashingLineEffect::Impl::onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) {
 957     const DashingLineEffect& de = args.fGeomProc.cast<DashingLineEffect>();
 958
 959     GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
 960     GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
 961     GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
 962
 963     // emit attributes
 964     varyingHandler->emitAttributes(de);
 965
 966     // XY refers to dashPos, Z is the dash interval length
 967     GrGLSLVarying inDashParams(SkSLType::kFloat3);
 968     varyingHandler->addVarying("DashParams", &inDashParams);
 969     vertBuilder->codeAppendf("%s = %s;", inDashParams.vsOut(), de.fInDashParams.name());
 970
 971     // The rect uniform's xyzw refer to (left + 0.5, top + 0.5, right - 0.5, bottom - 0.5),
 972     // respectively.
 973     GrGLSLVarying inRectParams(SkSLType::kFloat4);
 974     varyingHandler->addVarying("RectParams", &inRectParams);
 975     vertBuilder->codeAppendf("%s = %s;", inRectParams.vsOut(), de.fInRect.name());
 976
 977     GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
 978     // Setup pass through color
 979     fragBuilder->codeAppendf("half4 %s;", args.fOutputColor);
 980     this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor, &fColorUniform);
 981
 982     // Setup position
 983     WriteOutputPosition(vertBuilder, gpArgs, de.fInPosition.name());
 984     if (de.usesLocalCoords()) {
 985         WriteLocalCoord(vertBuilder,
 986                         uniformHandler,
 987                         *args.fShaderCaps,
 988                         gpArgs,
 989                         de.fInPosition.asShaderVar(),
 990                         de.fLocalMatrix,
 991                         &fLocalMatrixUniform);
 992     }
 993
 994     // transforms all points so that we can compare them to our test rect
 995     fragBuilder->codeAppendf("half xShifted = half(%s.x - floor(%s.x / %s.z) * %s.z);",
 996                              inDashParams.fsIn(), inDashParams.fsIn(), inDashParams.fsIn(),
 997                              inDashParams.fsIn());
 998     fragBuilder->codeAppendf("half2 fragPosShifted = half2(xShifted, half(%s.y));",
 999                              inDashParams.fsIn());
1000     if (de.fAAMode == AAMode::kCoverage) {
1001         // The amount of coverage removed in x and y by the edges is computed as a pair of negative
1002         // numbers, xSub and ySub.
1003         fragBuilder->codeAppend("half xSub, ySub;");
1004         fragBuilder->codeAppendf("xSub = half(min(fragPosShifted.x - %s.x, 0.0));",
1005                                  inRectParams.fsIn());
1006         fragBuilder->codeAppendf("xSub += half(min(%s.z - fragPosShifted.x, 0.0));",
1007                                  inRectParams.fsIn());
1008         fragBuilder->codeAppendf("ySub = half(min(fragPosShifted.y - %s.y, 0.0));",
1009                                  inRectParams.fsIn());
1010         fragBuilder->codeAppendf("ySub += half(min(%s.w - fragPosShifted.y, 0.0));",
1011                                  inRectParams.fsIn());
1012         // Now compute coverage in x and y and multiply them to get the fraction of the pixel
1013         // covered.
1014         fragBuilder->codeAppendf(
1015             "half alpha = (1.0 + max(xSub, -1.0)) * (1.0 + max(ySub, -1.0));");
1016     } else if (de.fAAMode == AAMode::kCoverageWithMSAA) {
1017         // For MSAA, we don't modulate the alpha by the Y distance, since MSAA coverage will handle
1018         // AA on the the top and bottom edges. The shader is only responsible for intra-dash alpha.
1019         fragBuilder->codeAppend("half xSub;");
1020         fragBuilder->codeAppendf("xSub = half(min(fragPosShifted.x - %s.x, 0.0));",
1021                                  inRectParams.fsIn());
1022         fragBuilder->codeAppendf("xSub += half(min(%s.z - fragPosShifted.x, 0.0));",
1023                                  inRectParams.fsIn());
1024         // Now compute coverage in x to get the fraction of the pixel covered.
1025         fragBuilder->codeAppendf("half alpha = (1.0 + max(xSub, -1.0));");
1026     } else {
1027         // Assuming the bounding geometry is tight so no need to check y values
1028         fragBuilder->codeAppendf("half alpha = 1.0;");
1029         fragBuilder->codeAppendf("alpha *= (fragPosShifted.x - %s.x) > -0.5 ? 1.0 : 0.0;",
1030                                  inRectParams.fsIn());
1031         fragBuilder->codeAppendf("alpha *= (%s.z - fragPosShifted.x) >= -0.5 ? 1.0 : 0.0;",
1032                                  inRectParams.fsIn());
1033     }
1034     fragBuilder->codeAppendf("half4 %s = half4(alpha);", args.fOutputCoverage);
1035 }
1036
1037 void DashingLineEffect::Impl::setData(const GrGLSLProgramDataManager& pdman,
1038                                       const GrShaderCaps& shaderCaps,
1039                                       const GrGeometryProcessor& geomProc) {
1040     const DashingLineEffect& de = geomProc.cast<DashingLineEffect>();
1041     if (de.fColor != fColor) {
1042         pdman.set4fv(fColorUniform, 1, de.fColor.vec());
1043         fColor = de.fColor;
1044     }
1045     SetTransform(pdman, shaderCaps, fLocalMatrixUniform, de.fLocalMatrix, &fLocalMatrix);
1046 }
1047
1048 //////////////////////////////////////////////////////////////////////////////
1049
1050 GrGeometryProcessor* DashingLineEffect::Make(SkArenaAlloc* arena,
1051                                              const SkPMColor4f& color,
1052                                              AAMode aaMode,
1053                                              const SkMatrix& localMatrix,
1054                                              bool usesLocalCoords) {
1055     return arena->make([&](void* ptr) {
1056         return new (ptr) DashingLineEffect(color, aaMode, localMatrix, usesLocalCoords);
1057     });
1058 }
1059
1060 void DashingLineEffect::addToKey(const GrShaderCaps& caps, KeyBuilder* b) const {
1061     uint32_t key = 0;
1062     key |= fUsesLocalCoords ? 0x1 : 0x0;
1063     key |= static_cast<int>(fAAMode) << 1;
1064     key |= ProgramImpl::ComputeMatrixKey(caps, fLocalMatrix) << 3;
1065     b->add32(key);
1066 }
1067
1068 std::unique_ptr<GrGeometryProcessor::ProgramImpl> DashingLineEffect::makeProgramImpl(
1069         const GrShaderCaps&) const {
1070     return std::make_unique<Impl>();
1071 }
1072
1073 DashingLineEffect::DashingLineEffect(const SkPMColor4f& color,
1074                                      AAMode aaMode,
1075                                      const SkMatrix& localMatrix,
1076                                      bool usesLocalCoords)
1077         : INHERITED(kDashingLineEffect_ClassID)
1078         , fColor(color)
1079         , fLocalMatrix(localMatrix)
1080         , fUsesLocalCoords(usesLocalCoords)
1081         , fAAMode(aaMode) {
1082     fInPosition = {"inPosition", kFloat2_GrVertexAttribType, SkSLType::kFloat2};
1083     fInDashParams = {"inDashParams", kFloat3_GrVertexAttribType, SkSLType::kHalf3};
1084     fInRect = {"inRect", kFloat4_GrVertexAttribType, SkSLType::kHalf4};
1085     this->setVertexAttributesWithImplicitOffsets(&fInPosition, 3);
1086 }
1087
1088 GR_DEFINE_GEOMETRY_PROCESSOR_TEST(DashingLineEffect);
1089
1090 #if GR_TEST_UTILS
1091 GrGeometryProcessor* DashingLineEffect::TestCreate(GrProcessorTestData* d) {
1092     AAMode aaMode = static_cast<AAMode>(d->fRandom->nextULessThan(kAAModeCnt));
1093     GrColor color = GrTest::RandomColor(d->fRandom);
1094     SkMatrix matrix = GrTest::TestMatrix(d->fRandom);
1095     return DashingLineEffect::Make(d->allocator(),
1096                                    SkPMColor4f::FromBytes_RGBA(color),
1097                                    aaMode,
1098                                    matrix,
1099                                    d->fRandom->nextBool());
1100 }
1101
1102 #endif
1103 //////////////////////////////////////////////////////////////////////////////
1104
1105 GrGeometryProcessor* make_dash_gp(SkArenaAlloc* arena,
1106                                   const SkPMColor4f& color,
1107                                   AAMode aaMode,
1108                                   DashCap cap,
1109                                   const SkMatrix& viewMatrix,
1110                                   bool usesLocalCoords) {
1111     SkMatrix invert;
1112     if (usesLocalCoords && !viewMatrix.invert(&invert)) {
1113         SkDebugf("Failed to invert\n");
1114         return nullptr;
1115     }
1116
1117     switch (cap) {
1118         case kRound_DashCap:
1119             return DashingCircleEffect::Make(arena, color, aaMode, invert, usesLocalCoords);
1120         case kNonRound_DashCap:
1121             return DashingLineEffect::Make(arena, color, aaMode, invert, usesLocalCoords);
1122     }
1123     return nullptr;
1124 }
1125
1126 } // anonymous namespace
1127
1128 /////////////////////////////////////////////////////////////////////////////////////////////////
1129
1130 GrOp::Owner MakeDashLineOp(GrRecordingContext* context,
1131                            GrPaint&& paint,
1132                            const SkMatrix& viewMatrix,
1133                            const SkPoint pts[2],
1134                            AAMode aaMode,
1135                            const GrStyle& style,
1136                            const GrUserStencilSettings* stencilSettings) {
1137     SkASSERT(CanDrawDashLine(pts, style, viewMatrix));
1138     const SkScalar* intervals = style.dashIntervals();
1139     SkScalar phase = style.dashPhase();
1140
1141     SkPaint::Cap cap = style.strokeRec().getCap();
1142
1143     DashOpImpl::LineData lineData;
1144     lineData.fSrcStrokeWidth = style.strokeRec().getWidth();
1145
1146     // the phase should be normalized to be [0, sum of all intervals)
1147     SkASSERT(phase >= 0 && phase < intervals[0] + intervals[1]);
1148
1149     // Rotate the src pts so they are aligned horizontally with pts[0].fX < pts[1].fX
1150     if (pts[0].fY != pts[1].fY || pts[0].fX > pts[1].fX) {
1151         SkMatrix rotMatrix;
1152         align_to_x_axis(pts, &rotMatrix, lineData.fPtsRot);
1153         if (!rotMatrix.invert(&lineData.fSrcRotInv)) {
1154             SkDebugf("Failed to create invertible rotation matrix!\n");
1155             return nullptr;
1156         }
1157     } else {
1158         lineData.fSrcRotInv.reset();
1159         memcpy(lineData.fPtsRot, pts, 2 * sizeof(SkPoint));
1160     }
1161
1162     // Scale corrections of intervals and stroke from view matrix
1163     calc_dash_scaling(&lineData.fParallelScale, &lineData.fPerpendicularScale, viewMatrix, pts);
1164     if (SkScalarNearlyZero(lineData.fParallelScale) ||
1165         SkScalarNearlyZero(lineData.fPerpendicularScale)) {
1166         return nullptr;
1167     }
1168
1169     SkScalar offInterval = intervals[1] * lineData.fParallelScale;
1170     SkScalar strokeWidth = lineData.fSrcStrokeWidth * lineData.fPerpendicularScale;
1171
1172     if (SkPaint::kSquare_Cap == cap && 0 != lineData.fSrcStrokeWidth) {
1173         // add cap to on interval and remove from off interval
1174         offInterval -= strokeWidth;
1175     }
1176
1177     // TODO we can do a real rect call if not using fulldash(ie no off interval, not using AA)
1178     bool fullDash = offInterval > 0.f || aaMode != AAMode::kNone;
1179
1180     lineData.fViewMatrix = viewMatrix;
1181     lineData.fPhase = phase;
1182     lineData.fIntervals[0] = intervals[0];
1183     lineData.fIntervals[1] = intervals[1];
1184
1185     return DashOpImpl::Make(context, std::move(paint), lineData, cap, aaMode, fullDash,
1186                             stencilSettings);
1187 }
1188
1189 // Returns whether or not the gpu can fast path the dash line effect.
1190 bool CanDrawDashLine(const SkPoint pts[2], const GrStyle& style, const SkMatrix& viewMatrix) {
1191     // Pts must be either horizontal or vertical in src space
1192     if (pts[0].fX != pts[1].fX && pts[0].fY != pts[1].fY) {
1193         return false;
1194     }
1195
1196     // May be able to relax this to include skew. As of now cannot do perspective
1197     // because of the non uniform scaling of bloating a rect
1198     if (!viewMatrix.preservesRightAngles()) {
1199         return false;
1200     }
1201
1202     if (!style.isDashed() || 2 != style.dashIntervalCnt()) {
1203         return false;
1204     }
1205
1206     const SkScalar* intervals = style.dashIntervals();
1207     if (0 == intervals[0] && 0 == intervals[1]) {
1208         return false;
1209     }
1210
1211     SkPaint::Cap cap = style.strokeRec().getCap();
1212     if (SkPaint::kRound_Cap == cap) {
1213         // Current we don't support round caps unless the on interval is zero
1214         if (intervals[0] != 0.f) {
1215             return false;
1216         }
1217         // If the width of the circle caps in greater than the off interval we will pick up unwanted
1218         // segments of circles at the start and end of the dash line.
1219         if (style.strokeRec().getWidth() > intervals[1]) {
1220             return false;
1221         }
1222     }
1223
1224     return true;
1225 }
1226
1227 } // namespace skgpu::v1::DashOp
1228
1229 #if GR_TEST_UTILS
1230
1231 #include "src/gpu/ganesh/GrDrawOpTest.h"
1232
1233 GR_DRAW_OP_TEST_DEFINE(DashOpImpl) {
1234     SkMatrix viewMatrix = GrTest::TestMatrixPreservesRightAngles(random);
1235     AAMode aaMode;
1236     do {
1237         aaMode = static_cast<AAMode>(random->nextULessThan(kAAModeCnt));
1238     } while (AAMode::kCoverageWithMSAA == aaMode && numSamples <= 1);
1239
1240     // We can only dash either horizontal or vertical lines
1241     SkPoint pts[2];
1242     if (random->nextBool()) {
1243         // vertical
1244         pts[0].fX = 1.f;
1245         pts[0].fY = random->nextF() * 10.f;
1246         pts[1].fX = 1.f;
1247         pts[1].fY = random->nextF() * 10.f;
1248     } else {
1249         // horizontal
1250         pts[0].fX = random->nextF() * 10.f;
1251         pts[0].fY = 1.f;
1252         pts[1].fX = random->nextF() * 10.f;
1253         pts[1].fY = 1.f;
1254     }
1255
1256     // pick random cap
1257     SkPaint::Cap cap = SkPaint::Cap(random->nextULessThan(SkPaint::kCapCount));
1258
1259     SkScalar intervals[2];
1260
1261     // We can only dash with the following intervals
1262     enum Intervals {
1263         kOpenOpen_Intervals ,
1264         kOpenClose_Intervals,
1265         kCloseOpen_Intervals,
1266     };
1267
1268     Intervals intervalType = SkPaint::kRound_Cap == cap ?
1269                              kOpenClose_Intervals :
1270                              Intervals(random->nextULessThan(kCloseOpen_Intervals + 1));
1271     static const SkScalar kIntervalMin = 0.1f;
1272     static const SkScalar kIntervalMinCircles = 1.f; // Must be >= to stroke width
1273     static const SkScalar kIntervalMax = 10.f;
1274     switch (intervalType) {
1275         case kOpenOpen_Intervals:
1276             intervals[0] = random->nextRangeScalar(kIntervalMin, kIntervalMax);
1277             intervals[1] = random->nextRangeScalar(kIntervalMin, kIntervalMax);
1278             break;
1279         case kOpenClose_Intervals: {
1280             intervals[0] = 0.f;
1281             SkScalar min = SkPaint::kRound_Cap == cap ? kIntervalMinCircles : kIntervalMin;
1282             intervals[1] = random->nextRangeScalar(min, kIntervalMax);
1283             break;
1284         }
1285         case kCloseOpen_Intervals:
1286             intervals[0] = random->nextRangeScalar(kIntervalMin, kIntervalMax);
1287             intervals[1] = 0.f;
1288             break;
1289
1290     }
1291
1292     // phase is 0 < sum (i0, i1)
1293     SkScalar phase = random->nextRangeScalar(0, intervals[0] + intervals[1]);
1294
1295     SkPaint p;
1296     p.setStyle(SkPaint::kStroke_Style);
1297     p.setStrokeWidth(SkIntToScalar(1));
1298     p.setStrokeCap(cap);
1299     p.setPathEffect(GrTest::TestDashPathEffect::Make(intervals, 2, phase));
1300
1301     GrStyle style(p);
1302
1303     return skgpu::v1::DashOp::MakeDashLineOp(context, std::move(paint), viewMatrix, pts, aaMode,
1304                                              style, GrGetRandomStencil(random, context));
1305 }
1306
1307 #endif // GR_TEST_UTILS