Implement support for PorterDuff's blending modes.
The blending modes are currently hooked up only when drawing filled rects but the
code is reusable for other primitives. This will allow implementation of saveLayer().
This method is required to support the fade effects used throughout the standard
Android UI.
Change-Id: I396023d123436f16cdafc606e358e4eb80c9df2c
diff --git a/libs/hwui/OpenGLRenderer.h b/libs/hwui/OpenGLRenderer.h
index 1e031b8..85fa541 100644
--- a/libs/hwui/OpenGLRenderer.h
+++ b/libs/hwui/OpenGLRenderer.h
@@ -53,6 +53,15 @@
float texture[2];
}; // struct TextureVertex
+/**
+ * Structure mapping Skia xfermodes to OpenGL blending factors.
+ */
+struct Blender {
+ SkXfermode::Mode mode;
+ GLenum src;
+ GLenum dst;
+}; // struct Blender
+
///////////////////////////////////////////////////////////////////////////////
// Renderer
///////////////////////////////////////////////////////////////////////////////
@@ -125,8 +134,10 @@
* @param right The right coordinate of the rectangle
* @param bottom The bottom coordinate of the rectangle
* @param color The rectangle's ARGB color, defined as a packed 32 bits word
+ * @param mode The Skia xfermode to use
*/
- void drawColorRect(float left, float top, float right, float bottom, int color);
+ void drawColorRect(float left, float top, float right, float bottom,
+ int color, SkXfermode::Mode mode);
/**
* Draws a textured rectangle with the specified texture. The specified coordinates
@@ -142,6 +153,19 @@
void drawTextureRect(float left, float top, float right, float bottom, GLuint texture,
float alpha);
+ /**
+ * Resets the texture coordinates stored in mDrawTextureVertices. Setting the values
+ * back to default is achieved by calling:
+ *
+ * resetDrawTextureTexCoords(0.0f, 1.0f, 1.0f, 0.0f);
+ *
+ * @param u1 The left coordinate of the texture
+ * @param v1 The bottom coordinate of the texture
+ * @param u2 The right coordinate of the texture
+ * @param v2 The top coordinate of the texture
+ */
+ void resetDrawTextureTexCoords(float u1, float v1, float u2, float v2);
+
// Dimensions of the drawing surface
int mWidth, mHeight;
@@ -161,6 +185,9 @@
// Shaders
sp<DrawColorProgram> mDrawColorShader;
sp<DrawTextureProgram> mDrawTextureShader;
+
+ // Used to draw textured quads
+ TextureVertex mDrawTextureVertices[4];
}; // class OpenGLRenderer
}; // namespace uirenderer