Add implementations for saveLayerAlpha() and textured rects.

Even though there's an implementation for textured rects, drawBitmap() is not
hooked up yet as it will require a good texture cache.

This method is implemented using FBOs. There's currently an issue either in the
driver or in the Canvas renderer that forces the FBO to be fullscreen, which is
extremely expensive and yields terrible performance.

Change-Id: I148419195e12d45653c60186938aa78c23a68e2c

3 files changed, 33 insertions, 3 deletions

diff --git a/libs/hwui/shaders/drawColor.frag b/libs/hwui/shaders/drawColor.frag
index f753abb..e84c47b 100644
--- a/libs/hwui/shaders/drawColor.frag
+++ b/libs/hwui/shaders/drawColor.frag
@@ -1,8 +1,6 @@
 SHADER_SOURCE(gDrawColorFragmentShader,
 
-precision mediump float;
-
-varying vec4 outColor;
+varying lowp vec4 outColor;
 
 void main(void) {
     gl_FragColor = outColor;
diff --git a/libs/hwui/shaders/drawTexture.frag b/libs/hwui/shaders/drawTexture.frag
new file mode 100644
index 0000000..5bd420e
--- /dev/null
+++ b/libs/hwui/shaders/drawTexture.frag
@@ -0,0 +1,12 @@
+SHADER_SOURCE(gDrawTextureFragmentShader,
+
+varying lowp vec4 outColor;
+varying mediump vec2 outTexCoords;
+
+uniform sampler2D sampler;
+
+void main(void) {
+    gl_FragColor = texture2D(sampler, outTexCoords) * outColor;
+}
+
+);
diff --git a/libs/hwui/shaders/drawTexture.vert b/libs/hwui/shaders/drawTexture.vert
new file mode 100644
index 0000000..310a812
--- /dev/null
+++ b/libs/hwui/shaders/drawTexture.vert
@@ -0,0 +1,20 @@
+SHADER_SOURCE(gDrawTextureVertexShader,
+
+attribute vec4 position;
+attribute vec2 texCoords;
+attribute vec4 color;
+
+uniform mat4 projection;
+uniform mat4 modelView;
+uniform mat4 transform;
+
+varying vec4 outColor;
+varying vec2 outTexCoords;
+
+void main(void) {
+    outColor = color;
+    outTexCoords = texCoords;
+    gl_Position = projection * transform * modelView * position;
+}
+
+);