From cd0749144383d78a10a5df00e2e96e76456b412b Mon Sep 17 00:00:00 2001 From: bsalomon Date: Wed, 9 Dec 2015 10:33:51 -0800 Subject: [PATCH] Prevent overflow in length() in GLCircularRRectEffect BUG=chromium:477684 Review URL: https://codereview.chromium.org/1517483002 --- src/gpu/effects/GrRRectEffect.cpp | 124 +++++++++++++++++++------------------- 1 file changed, 63 insertions(+), 61 deletions(-) diff --git a/src/gpu/effects/GrRRectEffect.cpp b/src/gpu/effects/GrRRectEffect.cpp index f8c6a41..0b75875 100644 --- a/src/gpu/effects/GrRRectEffect.cpp +++ b/src/gpu/effects/GrRRectEffect.cpp @@ -162,11 +162,21 @@ void GLCircularRRectEffect::emitCode(EmitArgs& args) { kVec4f_GrSLType, kDefault_GrSLPrecision, "innerRect", &rectName); + // x is (r + .5) and y is 1/(r + .5) fRadiusPlusHalfUniform = uniformHandler->addUniform(GrGLSLUniformHandler::kFragment_Visibility, - kFloat_GrSLType, kDefault_GrSLPrecision, + kVec2f_GrSLType, kDefault_GrSLPrecision, "radiusPlusHalf", &radiusPlusHalfName); + // If we're on a device with a "real" mediump then the length calculation could overflow. + SkString clampedCircleDistance; + if (args.fGLSLCaps->floatPrecisionVaries()) { + clampedCircleDistance.printf("clamp(%s.x * (1.0 - length(dxy * %s.y)), 0.0, 1.0);", + radiusPlusHalfName, radiusPlusHalfName); + } else { + clampedCircleDistance.printf("clamp(%s.x - length(dxy), 0.0, 1.0);", radiusPlusHalfName); + } + GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder; const char* fragmentPos = fragBuilder->fragmentPosition(); // At each quarter-circle corner we compute a vector that is the offset of the fragment position @@ -186,103 +196,94 @@ void GLCircularRRectEffect::emitCode(EmitArgs& args) { // alphas together. switch (crre.getCircularCornerFlags()) { case CircularRRectEffect::kAll_CornerFlags: - fragBuilder->codeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos); - fragBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName); - fragBuilder->codeAppend("\t\tvec2 dxy = max(max(dxy0, dxy1), 0.0);\n"); - fragBuilder->codeAppendf("\t\tfloat alpha = clamp(%s - length(dxy), 0.0, 1.0);\n", - radiusPlusHalfName); + fragBuilder->codeAppendf("vec2 dxy0 = %s.xy - %s.xy;", rectName, fragmentPos); + fragBuilder->codeAppendf("vec2 dxy1 = %s.xy - %s.zw;", fragmentPos, rectName); + fragBuilder->codeAppend("vec2 dxy = max(max(dxy0, dxy1), 0.0);"); + fragBuilder->codeAppendf("float alpha = %s;", clampedCircleDistance.c_str()); break; case CircularRRectEffect::kTopLeft_CornerFlag: - fragBuilder->codeAppendf("\t\tvec2 dxy = max(%s.xy - %s.xy, 0.0);\n", + fragBuilder->codeAppendf("vec2 dxy = max(%s.xy - %s.xy, 0.0);", rectName, fragmentPos); - fragBuilder->codeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);", rectName, fragmentPos); - fragBuilder->codeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);", rectName, fragmentPos); - fragBuilder->codeAppendf( - "\t\tfloat alpha = bottomAlpha * rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n", - radiusPlusHalfName); + fragBuilder->codeAppendf("float alpha = bottomAlpha * rightAlpha * %s;", + clampedCircleDistance.c_str()); break; case CircularRRectEffect::kTopRight_CornerFlag: - fragBuilder->codeAppendf("\t\tvec2 dxy = max(vec2(%s.x - %s.z, %s.y - %s.y), 0.0);\n", + fragBuilder->codeAppendf("vec2 dxy = max(vec2(%s.x - %s.z, %s.y - %s.y), 0.0);", fragmentPos, rectName, rectName, fragmentPos); - fragBuilder->codeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);", fragmentPos, rectName); - fragBuilder->codeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);", rectName, fragmentPos); - fragBuilder->codeAppendf( - "\t\tfloat alpha = bottomAlpha * leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n", - radiusPlusHalfName); + fragBuilder->codeAppendf("float alpha = bottomAlpha * leftAlpha * %s;", + clampedCircleDistance.c_str()); break; case CircularRRectEffect::kBottomRight_CornerFlag: - fragBuilder->codeAppendf("\t\tvec2 dxy = max(%s.xy - %s.zw, 0.0);\n", + fragBuilder->codeAppendf("vec2 dxy = max(%s.xy - %s.zw, 0.0);", fragmentPos, rectName); - fragBuilder->codeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);", fragmentPos, rectName); - fragBuilder->codeAppendf("\t\tfloat topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);", fragmentPos, rectName); - fragBuilder->codeAppendf( - "\t\tfloat alpha = topAlpha * leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n", - radiusPlusHalfName); + fragBuilder->codeAppendf("float alpha = topAlpha * leftAlpha * %s;", + clampedCircleDistance.c_str()); break; case CircularRRectEffect::kBottomLeft_CornerFlag: - fragBuilder->codeAppendf("\t\tvec2 dxy = max(vec2(%s.x - %s.x, %s.y - %s.w), 0.0);\n", + fragBuilder->codeAppendf("vec2 dxy = max(vec2(%s.x - %s.x, %s.y - %s.w), 0.0);", rectName, fragmentPos, fragmentPos, rectName); - fragBuilder->codeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);", rectName, fragmentPos); - fragBuilder->codeAppendf("\t\tfloat topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);", fragmentPos, rectName); - fragBuilder->codeAppendf( - "\t\tfloat alpha = topAlpha * rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n", - radiusPlusHalfName); + fragBuilder->codeAppendf("float alpha = topAlpha * rightAlpha * %s;", + clampedCircleDistance.c_str()); break; case CircularRRectEffect::kLeft_CornerFlags: - fragBuilder->codeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos); - fragBuilder->codeAppendf("\t\tfloat dy1 = %s.y - %s.w;\n", fragmentPos, rectName); - fragBuilder->codeAppend("\t\tvec2 dxy = max(vec2(dxy0.x, max(dxy0.y, dy1)), 0.0);\n"); - fragBuilder->codeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n", + fragBuilder->codeAppendf("vec2 dxy0 = %s.xy - %s.xy;", rectName, fragmentPos); + fragBuilder->codeAppendf("float dy1 = %s.y - %s.w;", fragmentPos, rectName); + fragBuilder->codeAppend("vec2 dxy = max(vec2(dxy0.x, max(dxy0.y, dy1)), 0.0);"); + fragBuilder->codeAppendf("float rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);", rectName, fragmentPos); - fragBuilder->codeAppendf( - "\t\tfloat alpha = rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n", - radiusPlusHalfName); + fragBuilder->codeAppendf("float alpha = rightAlpha * %s;", + clampedCircleDistance.c_str()); break; case CircularRRectEffect::kTop_CornerFlags: - fragBuilder->codeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos); - fragBuilder->codeAppendf("\t\tfloat dx1 = %s.x - %s.z;\n", fragmentPos, rectName); - fragBuilder->codeAppend("\t\tvec2 dxy = max(vec2(max(dxy0.x, dx1), dxy0.y), 0.0);\n"); - fragBuilder->codeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n", + fragBuilder->codeAppendf("vec2 dxy0 = %s.xy - %s.xy;", rectName, fragmentPos); + fragBuilder->codeAppendf("float dx1 = %s.x - %s.z;", fragmentPos, rectName); + fragBuilder->codeAppend("vec2 dxy = max(vec2(max(dxy0.x, dx1), dxy0.y), 0.0);"); + fragBuilder->codeAppendf("float bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);", rectName, fragmentPos); - fragBuilder->codeAppendf( - "\t\tfloat alpha = bottomAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n", - radiusPlusHalfName); + fragBuilder->codeAppendf("float alpha = bottomAlpha * %s;", + clampedCircleDistance.c_str()); break; case CircularRRectEffect::kRight_CornerFlags: - fragBuilder->codeAppendf("\t\tfloat dy0 = %s.y - %s.y;\n", rectName, fragmentPos); - fragBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName); - fragBuilder->codeAppend("\t\tvec2 dxy = max(vec2(dxy1.x, max(dy0, dxy1.y)), 0.0);\n"); - fragBuilder->codeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float dy0 = %s.y - %s.y;", rectName, fragmentPos); + fragBuilder->codeAppendf("vec2 dxy1 = %s.xy - %s.zw;", fragmentPos, rectName); + fragBuilder->codeAppend("vec2 dxy = max(vec2(dxy1.x, max(dy0, dxy1.y)), 0.0);"); + fragBuilder->codeAppendf("float leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);", fragmentPos, rectName); - fragBuilder->codeAppendf( - "\t\tfloat alpha = leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n", - radiusPlusHalfName); + fragBuilder->codeAppendf("float alpha = leftAlpha * %s;", + clampedCircleDistance.c_str()); break; case CircularRRectEffect::kBottom_CornerFlags: - fragBuilder->codeAppendf("\t\tfloat dx0 = %s.x - %s.x;\n", rectName, fragmentPos); - fragBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName); - fragBuilder->codeAppend("\t\tvec2 dxy = max(vec2(max(dx0, dxy1.x), dxy1.y), 0.0);\n"); - fragBuilder->codeAppendf("\t\tfloat topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);\n", + fragBuilder->codeAppendf("float dx0 = %s.x - %s.x;", rectName, fragmentPos); + fragBuilder->codeAppendf("vec2 dxy1 = %s.xy - %s.zw;", fragmentPos, rectName); + fragBuilder->codeAppend("vec2 dxy = max(vec2(max(dx0, dxy1.x), dxy1.y), 0.0);"); + fragBuilder->codeAppendf("float topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);", fragmentPos, rectName); - fragBuilder->codeAppendf( - "\t\tfloat alpha = topAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n", - radiusPlusHalfName); + fragBuilder->codeAppendf("float alpha = topAlpha * %s;", + clampedCircleDistance.c_str()); break; } if (kInverseFillAA_GrProcessorEdgeType == crre.getEdgeType()) { - fragBuilder->codeAppend("\t\talpha = 1.0 - alpha;\n"); + fragBuilder->codeAppend("alpha = 1.0 - alpha;"); } - fragBuilder->codeAppendf("\t\t%s = %s;\n", args.fOutputColor, + fragBuilder->codeAppendf("%s = %s;", args.fOutputColor, (GrGLSLExpr4(args.fInputColor) * GrGLSLExpr1("alpha")).c_str()); } @@ -367,7 +368,8 @@ void GLCircularRRectEffect::onSetData(const GrGLSLProgramDataManager& pdman, SkFAIL("Should have been one of the above cases."); } pdman.set4f(fInnerRectUniform, rect.fLeft, rect.fTop, rect.fRight, rect.fBottom); - pdman.set1f(fRadiusPlusHalfUniform, radius + 0.5f); + radius += 0.5f; + pdman.set2f(fRadiusPlusHalfUniform, radius, 1.f / radius); fPrevRRect = rrect; } } -- 2.7.4