Refactor Skia shaders handling.

With this change, Skia shaders can easily be applied to any mesh. This change also
supports ComposeShader. For instance, this can be used to blend a gradient and a
bitmap togehter and paint a string of text with the result.

Change-Id: I701c2f9cf7f89b2ff58005e8a1d0d80ccf4a4aea

4 files changed, 37 insertions, 73 deletions

diff --git a/graphics/java/android/graphics/BitmapShader.java b/graphics/java/android/graphics/BitmapShader.java
index 37b40e7..4c92942 100644
--- a/graphics/java/android/graphics/BitmapShader.java
+++ b/graphics/java/android/graphics/BitmapShader.java
@@ -22,21 +22,6 @@ package android.graphics;
  */
 public class BitmapShader extends Shader {
     /**
-     * We hold on just for the GC, since our native counterpart is using it.
-     * 
-     * @hide 
-     */
-    public Bitmap mBitmap;
-    /**
-     * @hide 
-     */
-    public int mTileX;
-    /**
-     * @hide 
-     */
-    public int mTileY;
-
-    /**
      * Call this to create a new shader that will draw with a bitmap.
      *
      * @param bitmap            The bitmap to use inside the shader
@@ -44,12 +29,13 @@ public class BitmapShader extends Shader {
      * @param tileY             The tiling mode for y to draw the bitmap in.
      */
     public BitmapShader(Bitmap bitmap, TileMode tileX, TileMode tileY) {
-        mBitmap = bitmap;
-        mTileX = tileX.nativeInt;
-        mTileY = tileY.nativeInt;
-        native_instance = nativeCreate(bitmap.ni(), mTileX, mTileY);
+        final int b = bitmap.ni();
+        native_instance = nativeCreate(b, tileX.nativeInt, tileY.nativeInt);
+        native_shader = nativePostCreate(native_instance, b, tileX.nativeInt, tileY.nativeInt);
     }
 
     private static native int nativeCreate(int native_bitmap, int shaderTileModeX,
-            int shaderTileModeY);    
+            int shaderTileModeY);
+    private static native int nativePostCreate(int native_shader, int native_bitmap,
+            int shaderTileModeX, int shaderTileModeY);
 }
diff --git a/graphics/java/android/graphics/ComposeShader.java b/graphics/java/android/graphics/ComposeShader.java
index a06d30b..9b57ea4 100644
--- a/graphics/java/android/graphics/ComposeShader.java
+++ b/graphics/java/android/graphics/ComposeShader.java
@@ -30,7 +30,9 @@ public class ComposeShader extends Shader {
     */
     public ComposeShader(Shader shaderA, Shader shaderB, Xfermode mode) {
         native_instance = nativeCreate1(shaderA.native_instance, shaderB.native_instance,
-                                        (mode != null) ? mode.native_instance : 0);
+                (mode != null) ? mode.native_instance : 0);
+        native_shader = nativePostCreate1(native_instance, shaderA.native_shader,
+                shaderB.native_shader, (mode != null) ? mode.native_instance : 0);
     }
 
     /** Create a new compose shader, given shaders A, B, and a combining PorterDuff mode.
@@ -42,10 +44,17 @@ public class ComposeShader extends Shader {
     */
     public ComposeShader(Shader shaderA, Shader shaderB, PorterDuff.Mode mode) {
         native_instance = nativeCreate2(shaderA.native_instance, shaderB.native_instance,
-                                        mode.nativeInt);
+                mode.nativeInt);
+        native_shader = nativePostCreate2(native_instance, shaderA.native_shader,
+                shaderB.native_shader, mode.nativeInt);
     }
 
-    private static native int nativeCreate1(int native_shaderA, int native_shaderB, int native_mode);
-    private static native int nativeCreate2(int native_shaderA, int native_shaderB, int porterDuffMode);
+    private static native int nativeCreate1(int native_shaderA, int native_shaderB,
+            int native_mode);
+    private static native int nativeCreate2(int native_shaderA, int native_shaderB,
+            int porterDuffMode);
+    private static native int nativePostCreate1(int native_shader, int native_skiaShaderA,
+            int native_skiaShaderB, int native_mode);
+    private static native int nativePostCreate2(int native_shader, int native_skiaShaderA,
+            int native_skiaShaderB, int porterDuffMode);
 }
-
diff --git a/graphics/java/android/graphics/LinearGradient.java b/graphics/java/android/graphics/LinearGradient.java
index fd57591..82ed199 100644
--- a/graphics/java/android/graphics/LinearGradient.java
+++ b/graphics/java/android/graphics/LinearGradient.java
@@ -17,28 +17,6 @@
 package android.graphics;
 
 public class LinearGradient extends Shader {
-    /**
-     * These fields are manipulated by the JNI layer, don't touch!
-     * @hide
-     */
-    public int bounds;
-    /**
-     * @hide
-     */
-    public int colors;
-    /**
-     * @hide
-     */
-    public int positions;
-    /**
-     * @hide
-     */
-    public int count;
-    /**
-     * @hide
-     */
-    public int tileMode;
-
 	/**	Create a shader that draws a linear gradient along a line.
         @param x0           The x-coordinate for the start of the gradient line
         @param y0           The y-coordinate for the start of the gradient line
@@ -59,8 +37,8 @@ public class LinearGradient extends Shader {
             throw new IllegalArgumentException("color and position arrays must be of equal length");
         }
         native_instance = nativeCreate1(x0, y0, x1, y1, colors, positions, tile.nativeInt);
-        count = colors.length;
-        tileMode = tile.nativeInt;
+        native_shader = nativePostCreate1(native_instance, x0, y0, x1, y1, colors, positions,
+                tile.nativeInt);
     }
 
 	/**	Create a shader that draws a linear gradient along a line.
@@ -75,21 +53,16 @@ public class LinearGradient extends Shader {
 	public LinearGradient(float x0, float y0, float x1, float y1,
                           int color0, int color1, TileMode tile) {
         native_instance = nativeCreate2(x0, y0, x1, y1, color0, color1, tile.nativeInt);
-        count = 2;
-        tileMode = tile.nativeInt;
-    }
-    
-    protected void finalize() throws Throwable {
-        try {
-            super.finalize();
-        } finally {
-            nativeDestructor(native_instance);
-        }
+        native_shader = nativePostCreate2(native_instance, x0, y0, x1, y1, color0, color1,
+                tile.nativeInt);
     }
 
-    private native void nativeDestructor(int native_shader);
 	private native int nativeCreate1(float x0, float y0, float x1, float y1,
             int colors[], float positions[], int tileMode);
 	private native int nativeCreate2(float x0, float y0, float x1, float y1,
             int color0, int color1, int tileMode);
+    private native int nativePostCreate1(int native_shader, float x0, float y0, float x1, float y1,
+            int colors[], float positions[], int tileMode);
+    private native int nativePostCreate2(int native_shader, float x0, float y0, float x1, float y1,
+            int color0, int color1, int tileMode);
 }
diff --git a/graphics/java/android/graphics/Shader.java b/graphics/java/android/graphics/Shader.java
index 86c71e3..b397662 100644
--- a/graphics/java/android/graphics/Shader.java
+++ b/graphics/java/android/graphics/Shader.java
@@ -24,18 +24,15 @@ package android.graphics;
  */
 public class Shader {
     /**
-     * Local matrix native instance.
-     * 
-     * @hide
-     */
-    public int mLocalMatrix;
-
-    /**
      * This is set by subclasses, but don't make it public.
      * 
      * @hide 
      */
     public int native_instance;
+    /**
+     * @hide
+     */
+    public int native_shader;
 
     public enum TileMode {
         /**
@@ -74,21 +71,20 @@ public class Shader {
      * @param localM The shader's new local matrix, or null to specify identity
      */
     public void setLocalMatrix(Matrix localM) {
-        mLocalMatrix = localM != null ? localM.native_instance : 0;
-        nativeSetLocalMatrix(native_instance, mLocalMatrix);
+        nativeSetLocalMatrix(native_instance, native_shader, localM.native_instance);
     }
 
     protected void finalize() throws Throwable {
         try {
             super.finalize();
         } finally {
-            nativeDestructor(native_instance);
+            nativeDestructor(native_instance, native_shader);
         }
     }
 
-    private static native void nativeDestructor(int native_shader);
+    private static native void nativeDestructor(int native_shader, int native_skiaShader);
     private static native boolean nativeGetLocalMatrix(int native_shader,
-                                                       int matrix_instance);
+            int matrix_instance); 
     private static native void nativeSetLocalMatrix(int native_shader,
-                                                    int matrix_instance);
+            int native_skiaShader, int matrix_instance);
 }