gm/textblobtransforms.cpp

   1 /*
   2  * Copyright 2015 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 "gm.h"
   9 #include "sk_tool_utils.h"
  10
  11 #include "Resources.h"
  12 #include "SkCanvas.h"
  13 #include "SkGradientShader.h"
  14 #include "SkStream.h"
  15 #include "SkTextBlob.h"
  16 #include "SkTypeface.h"
  17
  18 namespace skiagm {
  19 class TextBlobTransforms : public GM {
  20 public:
  21     // This gm tests that textblobs can be translated, rotated, and scaled
  22     TextBlobTransforms() {}
  23
  24 protected:
  25     void onOnceBeforeDraw() override {
  26         SkTextBlobBuilder builder;
  27
  28         // make textblob.  To stress distance fields, we choose sizes appropriately
  29         SkPaint paint;
  30         paint.setTextSize(162);
  31         const char* text = "A";
  32         sk_tool_utils::set_portable_typeface(&paint);
  33
  34         SkRect bounds;
  35         paint.measureText(text, strlen(text), &bounds);
  36         sk_tool_utils::add_to_text_blob(&builder, text, paint, 0, 0);
  37
  38         // Medium
  39         SkScalar xOffset = bounds.width() + 5;
  40         paint.setTextSize(72);
  41         text = "B";
  42         sk_tool_utils::add_to_text_blob(&builder, text, paint, xOffset, 0);
  43
  44         paint.measureText(text, strlen(text), &bounds);
  45         SkScalar yOffset = bounds.height();
  46
  47         // Small
  48         paint.setTextSize(32);
  49         text = "C";
  50         sk_tool_utils::add_to_text_blob(&builder, text, paint, xOffset, -yOffset - 10);
  51
  52         // build
  53         fBlob = builder.make();
  54     }
  55
  56     SkString onShortName() override {
  57         return SkString("textblobtransforms");
  58     }
  59
  60     SkISize onISize() override {
  61         return SkISize::Make(kWidth, kHeight);
  62     }
  63
  64     void onDraw(SkCanvas* canvas) override {
  65
  66         canvas->drawColor(sk_tool_utils::color_to_565(SK_ColorGRAY));
  67
  68         SkPaint paint;
  69
  70         SkRect bounds = fBlob->bounds();
  71         canvas->translate(20, 20);
  72
  73         // Colors were chosen to map to pairs of canonical colors.  The GPU Backend will cache A8
  74         // Texture Blobs based on the canonical color they map to.  Canonical colors are used to
  75         // create masks.  For A8 there are 8 of them.
  76         //SkColor colors[] = {SK_ColorCYAN, sk_tool_utils::color_to_565(SK_ColorLTGRAY), SK_ColorYELLOW, SK_ColorWHITE};
  77
  78         SkScalar xOffset = SkScalarCeilToScalar(bounds.width());
  79         SkScalar yOffset = SkScalarCeilToScalar(bounds.height());
  80         // first translate
  81         canvas->translate(xOffset, 2 * yOffset);
  82         canvas->drawTextBlob(fBlob, 0, 0, paint);
  83         canvas->translate(-xOffset, 0);
  84         canvas->drawTextBlob(fBlob, 0, 0, paint);
  85         canvas->translate(2 * xOffset, 0);
  86         canvas->drawTextBlob(fBlob, 0, 0, paint);
  87         canvas->translate(-xOffset, -yOffset);
  88         canvas->drawTextBlob(fBlob, 0, 0, paint);
  89         canvas->translate(0, 2 * yOffset);
  90         canvas->drawTextBlob(fBlob, 0, 0, paint);
  91
  92         // now rotate
  93         canvas->translate(4 * xOffset, -yOffset);
  94         canvas->rotate(180.f);
  95         canvas->drawTextBlob(fBlob, 0, 0, paint);
  96         canvas->rotate(-180.f);
  97         canvas->translate(0, -yOffset);
  98         canvas->rotate(-180.f);
  99         canvas->drawTextBlob(fBlob, 0, 0, paint);
 100         canvas->rotate(270.f);
 101         canvas->drawTextBlob(fBlob, 0, 0, paint);
 102         canvas->rotate(-90.f);
 103         canvas->translate(-xOffset, yOffset);
 104         canvas->rotate(-90.f);
 105         canvas->drawTextBlob(fBlob, 0, 0, paint);
 106         canvas->rotate(90.f);
 107
 108         // and scales
 109         canvas->translate(- 3 * xOffset, 3 * yOffset);
 110         canvas->scale(1.5f, 1.5f);
 111         canvas->drawTextBlob(fBlob, 0, 0, paint);
 112         canvas->translate(xOffset, 0);
 113         canvas->scale(.25f, .25f);
 114         canvas->drawTextBlob(fBlob, 0, 0, paint);
 115         canvas->translate(xOffset, 0);
 116         canvas->scale(3.f, 2.f);
 117         canvas->drawTextBlob(fBlob, 0, 0, paint);
 118
 119         // finally rotates, scales, and translates together
 120         canvas->translate(xOffset, 0);
 121         canvas->rotate(23.f);
 122         canvas->scale(.33f, .5f);
 123         canvas->drawTextBlob(fBlob, 0, 0, paint);
 124
 125         canvas->rotate(-46.f);
 126         canvas->translate(xOffset, 0);
 127         canvas->scale(1.2f, 1.1f);
 128         canvas->drawTextBlob(fBlob, 0, 0, paint);
 129
 130         canvas->rotate(46.f);
 131         canvas->translate(xOffset, 0);
 132         canvas->scale(1.1f, 1.2f);
 133         canvas->drawTextBlob(fBlob, 0, 0, paint);
 134
 135         canvas->rotate(46.f);
 136         canvas->translate(xOffset, 0);
 137         canvas->scale(.95f, 1.1f);
 138         canvas->drawTextBlob(fBlob, 0, 0, paint);
 139
 140         canvas->rotate(46.f);
 141         canvas->translate(xOffset, 0);
 142         canvas->scale(1.3f, .7f);
 143         canvas->drawTextBlob(fBlob, 0, 0, paint);
 144
 145         canvas->rotate(46.f);
 146         canvas->translate(xOffset, 0);
 147         canvas->scale(.8f, 1.1f);
 148         canvas->drawTextBlob(fBlob, 0, 0, paint);
 149
 150         canvas->rotate(10.f);
 151         canvas->translate(xOffset, 0);
 152         canvas->scale(1.f, 5.f);
 153         canvas->drawTextBlob(fBlob, 0, 0, paint);
 154
 155         canvas->rotate(5.f);
 156         canvas->translate(xOffset, 0);
 157         canvas->scale(5.f, 1.f);
 158         canvas->drawTextBlob(fBlob, 0, 0, paint);
 159     }
 160
 161 private:
 162     sk_sp<SkTextBlob> fBlob;
 163
 164     static constexpr int kWidth = 1000;
 165     static constexpr int kHeight = 1200;
 166
 167     typedef GM INHERITED;
 168 };
 169
 170 //////////////////////////////////////////////////////////////////////////////
 171
 172 DEF_GM(return new TextBlobTransforms;)
 173 }