3 files changed, 34 insertions, 10 deletions
diff --git a/WebCore/platform/graphics/android/GLUtils.cpp b/WebCore/platform/graphics/android/GLUtils.cpp
index 1c84fe2..0923c54 100644
--- a/WebCore/platform/graphics/android/GLUtils.cpp
+++ b/WebCore/platform/graphics/android/GLUtils.cpp
@@ -67,16 +67,17 @@ void GLUtils::toGLMatrix(GLfloat* flattened, const TransformationMatrix& m) {
 void GLUtils::setOrthographicMatrix(TransformationMatrix& ortho, float left, float top,
                                     float right, float bottom, float nearZ, float farZ) {
     float deltaX = right - left;
-    float deltaY = bottom - top;
+    float deltaY = top - bottom;
     float deltaZ = farZ - nearZ;
+    if (!deltaX || !deltaY || !deltaZ)
+        return;
 
     ortho.setM11(2.0f / deltaX);
-    ortho.setM22(2.0 / deltaY);
-    ortho.setM33(2.0f / deltaZ);
     ortho.setM41(-(right + left) / deltaX);
+    ortho.setM22(2.0f / deltaY);
     ortho.setM42(-(top + bottom) / deltaY);
-    ortho.setM43(-(farZ + nearZ) / deltaZ);
-    ortho.setM44(1);
+    ortho.setM33(-2.0f / deltaZ);
+    ortho.setM43(-(nearZ + farZ) / deltaZ);
 }
 
 /////////////////////////////////////////////////////////////////////////////////////////
diff --git a/WebCore/platform/graphics/android/ShaderProgram.cpp b/WebCore/platform/graphics/android/ShaderProgram.cpp
index aa41a48..2195bd4 100644
--- a/WebCore/platform/graphics/android/ShaderProgram.cpp
+++ b/WebCore/platform/graphics/android/ShaderProgram.cpp
@@ -149,11 +149,7 @@ void ShaderProgram::setViewport(SkRect& viewport) {
     TransformationMatrix ortho;
     GLUtils::setOrthographicMatrix(ortho, viewport.fLeft, viewport.fTop,
                                    viewport.fRight, viewport.fBottom, -1000, 1000);
-    TransformationMatrix invert;
-    invert.scale3d(1.0, -1.0, 1.0);
-    TransformationMatrix total = invert;
-    total.multLeft(ortho);
-    m_projectionMatrix = total;
+    m_projectionMatrix = ortho;
 }
 
 void ShaderProgram::setProjectionMatrix(SkRect& geometry) {
@@ -184,6 +180,31 @@ void ShaderProgram::drawQuad(SkRect& geometry, int textureId, float opacity) {
     glUniform1f(alpha(), opacity);
 
     glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+
+    GLUtils::checkGlError("drawQuad");
+}
+
+void ShaderProgram::drawLayerQuad(const TransformationMatrix& drawMatrix,
+                                  SkRect& geometry, int textureId, float opacity) {
+
+    TransformationMatrix renderMatrix = drawMatrix;
+    renderMatrix.scale3d(geometry.width(), geometry.height(), 1);
+    renderMatrix.multiply(m_projectionMatrix);
+
+    GLfloat projectionMatrix[16];
+    GLUtils::toGLMatrix(projectionMatrix, renderMatrix);
+    glUniformMatrix4fv(m_hProjectionMatrix, 1, GL_FALSE, projectionMatrix);
+
+    glActiveTexture(GL_TEXTURE0);
+    glBindTexture(GL_TEXTURE_2D, textureId);
+
+    glBindBuffer(GL_ARRAY_BUFFER, m_textureBuffer[0]);
+    glEnableVertexAttribArray(1);
+    glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 0, 0);
+    glBindAttribLocation(program(), 1, "vPosition");
+    glUniform1f(alpha(), opacity);
+
+    glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 }
 
 } // namespace WebCore
diff --git a/WebCore/platform/graphics/android/ShaderProgram.h b/WebCore/platform/graphics/android/ShaderProgram.h
index 4a8e96e..93a6d4c 100644
--- a/WebCore/platform/graphics/android/ShaderProgram.h
+++ b/WebCore/platform/graphics/android/ShaderProgram.h
@@ -36,6 +36,8 @@ class ShaderProgram {
   // Drawing
   void setViewport(SkRect& viewport);
   void drawQuad(SkRect& geometry, int textureId, float opacity);
+  void drawLayerQuad(const TransformationMatrix& drawMatrix,
+                     SkRect& geometry, int textureId, float opacity);
 
  private:
   GLuint loadShader(GLenum shaderType, const char* pSource);