Add plumbing to support gradients in OpenGL renderer.

The LinearGradient class keeps a copy of the various parameters that
define the gradient. The copies are native arrays to avoid copying
Java arrays on every draw call. The gradient code path is implemented
until OpenGLRenderer::drawRect() (see TODO.) The actual gradient
implementation will be added in a latter change.

Change-Id: I9300d250ef5e2e9c2e097c3116ee71dfc9d752d8

1 files changed, 17 insertions, 2 deletions

diff --git a/libs/hwui/OpenGLRenderer.cpp b/libs/hwui/OpenGLRenderer.cpp
index 0bf0e89..1431563 100644
--- a/libs/hwui/OpenGLRenderer.cpp
+++ b/libs/hwui/OpenGLRenderer.cpp
@@ -528,7 +528,7 @@ void OpenGLRenderer::resetShader() {
 
 void OpenGLRenderer::setupBitmapShader(SkBitmap* bitmap, SkShader::TileMode tileX,
         SkShader::TileMode tileY, SkMatrix* matrix, bool hasAlpha) {
-    mShader = kShaderBitmap;
+    mShader = OpenGLRenderer::kShaderBitmap;
     mShaderBlend = hasAlpha;
     mShaderBitmap = bitmap;
     mShaderTileX = tileX;
@@ -536,6 +536,18 @@ void OpenGLRenderer::setupBitmapShader(SkBitmap* bitmap, SkShader::TileMode tile
     mShaderMatrix = matrix;
 }
 
+void OpenGLRenderer::setupLinearGradientShader(float* bounds, uint32_t* colors,
+        float* positions, SkShader::TileMode tileMode, SkMatrix* matrix, bool hasAlpha) {
+    mShader = OpenGLRenderer::kShaderLinearGradient;
+    mShaderBlend = hasAlpha;
+    mShaderTileX = tileMode;
+    mShaderTileY = tileMode;
+    mShaderMatrix = matrix;
+    mShaderBounds = bounds;
+    mShaderColors = colors;
+    mShaderPositions = positions;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // Drawing implementation
 ///////////////////////////////////////////////////////////////////////////////
@@ -555,9 +567,12 @@ void OpenGLRenderer::drawColorRect(float left, float top, float right, float bot
     const GLfloat b = a * ((color      ) & 0xFF) / 255.0f;
 
     switch (mShader) {
-        case kShaderBitmap:
+        case OpenGLRenderer::kShaderBitmap:
             drawBitmapShader(left, top, right, bottom, a, mode);
             return;
+        case OpenGLRenderer::kShaderLinearGradient:
+            // TODO: Generate gradient texture, set appropriate shader
+            break;
         default:
             break;
     }