Add program for linear gradient.
This change adds a new DrawLinearGradientProgram class to enable the drawing
of linear gradients. Two new vertex and fragment shaders are introduced,
based on DrawTextureProgram's shaders.
Change-Id: I885afc076bb6cef8cd3962ae21a086fa6a03bf96
diff --git a/libs/hwui/shaders/drawLinearGradient.vert b/libs/hwui/shaders/drawLinearGradient.vert
new file mode 100644
index 0000000..963dc87
--- /dev/null
+++ b/libs/hwui/shaders/drawLinearGradient.vert
@@ -0,0 +1,16 @@
+SHADER_SOURCE(gDrawLinearGradientVertexShader,
+
+attribute vec4 position;
+
+uniform float gradientLength;
+uniform vec2 gradient;
+uniform mat4 transform;
+
+varying float index;
+
+void main(void) {
+ gl_Position = transform * position;
+ index = dot(gl_Position.xy, gradient) * gradientLength;
+}
+
+);