[TextureMapper] Do texture transformation in vertex shader when copyi…

…ng texture

https://bugs.webkit.org/show_bug.cgi?id=261187

Reviewed by Fujii Hironori.

With the current implementation, transformation of texture coordinate
is performed in a fragment shader when copying texture or applying blur.

This change will move the transformation to vertex shader for better
performance.

* Source/WebCore/platform/graphics/texmap/TextureMapperGL.cpp:
(WebCore::TextureMapperGL::drawTextureCopy):
(WebCore::TextureMapperGL::drawBlurred):
* Source/WebCore/platform/graphics/texmap/TextureMapperShaderProgram.cpp:
* Source/WebCore/platform/graphics/texmap/TextureMapperShaderProgram.h:

Canonical link: https://commits.webkit.org/267687@main

Source/WebCore/platform/graphics/texmap/TextureMapperGL.cpp

@@ -794,6 +794,7 @@ void TextureMapperGL::drawTexturedQuadWithProgram(TextureMapperShaderProgram& pr
 void TextureMapperGL::drawTextureCopy(const BitmapTexture& sourceTexture, const FloatRect& sourceRect, const FloatRect& targetRect)
 {
     Ref<TextureMapperShaderProgram> program = data().getShaderProgram({ TextureMapperShaderProgram::TextureCopy });
+    IntSize textureSize = sourceTexture.contentSize();
 
     glUseProgram(program->programID());
 
@@ -809,11 +810,15 @@ void TextureMapperGL::drawTextureCopy(const BitmapTexture& sourceTexture, const
         0
     );
 
-    program->setMatrix(program->textureCopyMatrixLocation(), textureCopyMatrix);
+    program->setMatrix(program->textureSpaceMatrixLocation(), textureCopyMatrix);
 
-    glUniform2f(program->texelSizeLocation(), 1.f / sourceRect.width(), 1.f / sourceRect.height());
+    glUniform2f(program->texelSizeLocation(), 1.f / textureSize.width(), 1.f / textureSize.height());
 
-    drawTexturedQuadWithProgram(program.get(), static_cast<const BitmapTextureGL&>(sourceTexture).id(), 0, targetRect, TransformationMatrix(), 1);
+    glActiveTexture(GL_TEXTURE0);
+    glBindTexture(GL_TEXTURE_2D, static_cast<const BitmapTextureGL&>(sourceTexture).id());
+    glUniform1i(program->samplerLocation(), 0);
+
+    draw(targetRect, TransformationMatrix(), program.get(), GL_TRIANGLE_FAN, 0);
 }
 
 void TextureMapperGL::drawBlurred(const BitmapTexture& sourceTexture, const FloatRect& rect, float radius, Direction direction, bool alphaBlur)
@@ -822,9 +827,11 @@ void TextureMapperGL::drawBlurred(const BitmapTexture& sourceTexture, const Floa
         alphaBlur ? TextureMapperShaderProgram::AlphaBlur : TextureMapperShaderProgram::BlurFilter,
     });
 
+    IntSize textureSize = sourceTexture.contentSize();
+
     glUseProgram(program->programID());
 
-    glUniform2f(program->texelSizeLocation(), 1.f / rect.width(), 1.f / rect.height());
+    glUniform2f(program->texelSizeLocation(), 1.f / textureSize.width(), 1.f / textureSize.height());
 
     auto directionVector = direction == Direction::X ? FloatPoint(1, 0) : FloatPoint(0, 1);
     glUniform2f(program->blurDirectionLocation(), directionVector.x(), directionVector.y());
@@ -837,18 +844,22 @@ void TextureMapperGL::drawBlurred(const BitmapTexture& sourceTexture, const Floa
     auto textureBlurMatrix = TransformationMatrix::identity;
 
     textureBlurMatrix.scale3d(
-        double(rect.width()) / sourceTexture.contentSize().width(),
-        double(rect.height()) / sourceTexture.contentSize().height(),
+        double(rect.width()) / textureSize.width(),
+        double(rect.height()) / textureSize.height(),
         1
     ).translate3d(
-        double(rect.x()) / sourceTexture.contentSize().width(),
-        double(rect.y()) / sourceTexture.contentSize().height(),
+        double(rect.x()) / textureSize.width(),
+        double(rect.y()) / textureSize.height(),
         0
     );
 
-    program->setMatrix(program->textureBlurMatrixLocation(), textureBlurMatrix);
+    program->setMatrix(program->textureSpaceMatrixLocation(), textureBlurMatrix);
+
+    glActiveTexture(GL_TEXTURE0);
+    glBindTexture(GL_TEXTURE_2D, static_cast<const BitmapTextureGL&>(sourceTexture).id());
+    glUniform1i(program->samplerLocation(), 0);
 
-    drawTexturedQuadWithProgram(program.get(), static_cast<const BitmapTextureGL&>(sourceTexture).id(), 0, rect, TransformationMatrix(), 1);
+    draw(rect, TransformationMatrix(), program.get(), GL_TRIANGLE_FAN, 0);
 }
 
 RefPtr<BitmapTexture> TextureMapperGL::applyBlurFilter(RefPtr<BitmapTexture> sourceTexture, const BlurFilterOperation& blurFilter)

Source/WebCore/platform/graphics/texmap/TextureMapperShaderProgram.cpp

@@ -215,8 +215,6 @@ static const char* fragmentTemplateCommon =
         uniform int u_roundedRectNumber;
         uniform vec4 u_roundedRect[ROUNDED_RECT_ARRAY_SIZE];
         uniform mat4 u_roundedRectInverseTransformMatrix[ROUNDED_RECT_INVERSE_TRANSFORM_ARRAY_SIZE];
-        uniform mat4 u_textureCopyMatrix;
-        uniform mat4 u_textureBlurMatrix;
 
         void noop(inout vec4 dummyParameter) { }
         void noop(inout vec4 dummyParameter, vec2 texCoord) { }
@@ -348,40 +346,43 @@ static const char* fragmentTemplateCommon =
 
         void applyTextureCopy(inout vec4 color, vec2 texCoord)
         {
-            vec2 coord = clamp(texCoord, u_texelSize / 2., vec2(1., 1.) - u_texelSize / 2.);
-            coord = (u_textureCopyMatrix * vec4(coord, 0., 1.)).xy;
-            color = texture2D(s_sampler, coord);
-        }
+            vec2 min = (u_textureSpaceMatrix * vec4(0., 0., 0., 1.)).xy + u_texelSize / 2.;
+            vec2 max = (u_textureSpaceMatrix * vec4(1., 1., 0., 1.)).xy - u_texelSize / 2.;
 
-        vec4 sampleTextureClamp(sampler2D sampler, vec2 texCoord, vec2 offset, mat4 matrix)
-        {
-            vec2 coord = texCoord + offset;
-            coord = clamp(coord, u_texelSize / 2., vec2(1., 1.) - u_texelSize / 2.);
-            coord = (matrix * vec4(coord, 0., 1.)).xy;
-            return texture2D(sampler, coord);
+            vec2 coord = clamp(texCoord, min, max);
+
+            color = texture2D(s_sampler, coord);
         }
 
         void applyBlurFilter(inout vec4 color, vec2 texCoord)
         {
-            vec4 total = sampleTextureClamp(s_sampler, texCoord, vec2(0., 0.), u_textureBlurMatrix) * u_gaussianKernel[0];
+            vec2 step = u_blurDirection * u_texelSize;
+            vec2 min = (u_textureSpaceMatrix * vec4(0., 0., 0., 1.)).xy + u_texelSize / 2.;
+            vec2 max = (u_textureSpaceMatrix * vec4(1., 1., 0., 1.)).xy - u_texelSize / 2.;
+
+            vec4 total = texture2D(s_sampler, texCoord) * u_gaussianKernel[0];
 
             for (int i = 1; i < u_gaussianKernelHalfSize; i++) {
-                vec2 offset = u_blurDirection * u_texelSize * float(i);
-                total += sampleTextureClamp(s_sampler, texCoord, +offset, u_textureBlurMatrix) * u_gaussianKernel[i];
-                total += sampleTextureClamp(s_sampler, texCoord, -offset, u_textureBlurMatrix) * u_gaussianKernel[i];
+                vec2 offset = step * float(i);
+                total += texture2D(s_sampler, clamp(texCoord + offset, min, max)) * u_gaussianKernel[i];
+                total += texture2D(s_sampler, clamp(texCoord - offset, min, max)) * u_gaussianKernel[i];
             }
 
             color = total;
         }
 
         void applyAlphaBlur(inout vec4 color, vec2 texCoord)
         {
-            float total = sampleTextureClamp(s_sampler, texCoord, vec2(0., 0.), u_textureBlurMatrix).a * u_gaussianKernel[0];
+            vec2 step = u_blurDirection * u_texelSize;
+            vec2 min = (u_textureSpaceMatrix * vec4(0., 0., 0., 1.)).xy + u_texelSize / 2.;
+            vec2 max = (u_textureSpaceMatrix * vec4(1., 1., 0., 1.)).xy - u_texelSize / 2.;
+
+            float total = texture2D(s_sampler, texCoord).a * u_gaussianKernel[0];
 
             for (int i = 1; i < u_gaussianKernelHalfSize; i++) {
-                vec2 offset = u_blurDirection * u_texelSize * float(i);
-                total += sampleTextureClamp(s_sampler, texCoord, +offset, u_textureBlurMatrix).a * u_gaussianKernel[i];
-                total += sampleTextureClamp(s_sampler, texCoord, -offset, u_textureBlurMatrix).a * u_gaussianKernel[i];
+                vec2 offset = step * float(i);
+                total += texture2D(s_sampler, clamp(texCoord + offset, min, max)).a * u_gaussianKernel[i];
+                total += texture2D(s_sampler, clamp(texCoord - offset, min, max)).a * u_gaussianKernel[i];
             }
 
             color = vec4(0., 0., 0., total);

Source/WebCore/platform/graphics/texmap/TextureMapperShaderProgram.h

@@ -51,9 +51,7 @@ namespace WebCore {
     macro(blurDirection) \
     macro(roundedRectNumber) \
     macro(roundedRect) \
-    macro(roundedRectInverseTransformMatrix) \
-    macro(textureCopyMatrix) \
-    macro(textureBlurMatrix)
+    macro(roundedRectInverseTransformMatrix)
 
 #define TEXMAP_SAMPLER_VARIABLES(macro)           \
     macro(sampler)                                \