LayoutLib: Misc rendering fixes.

- always set up the stroke. Paint may not have the proper
  style when drawing lines. stroke should still be setup.

- Fixed vertical linear gradient. Old code generated
  a gradient ratio of NaN

- Fixed alpha rendering when using shaders. In that
  case the alpha channel from the paint color should be
  used in conjunction with the shader.

- Fixed miter limit. Java expects the value to be multiplied
  by the stroke width

- Fixed support for drawing ALPHA_8 bitmaps. Java2D doesn't
  have bitmaps with only alpha channels, so we keep using
  ARGB bitmaps but when drawing them into a bitmap we erase
  the color information.

Change-Id: I4f04341fc843e3f7dadd1fdbf709b11a4f1e24b9

3 files changed, 29 insertions, 20 deletions

diff --git a/tests/HwAccelerationTest/res/layout/_lines.xml b/tests/HwAccelerationTest/res/layout/_lines.xml
new file mode 100644
index 0000000..00f2556
--- /dev/null
+++ b/tests/HwAccelerationTest/res/layout/_lines.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<com.android.test.hwui.LinesActivity.LinesView
+  xmlns:android="http://schemas.android.com/apk/res/android"
+  android:layout_width="fill_parent"
+  android:layout_height="fill_parent">
+</com.android.test.hwui.LinesActivity.LinesView>
diff --git a/tests/HwAccelerationTest/src/com/android/test/hwui/LinesActivity.java b/tests/HwAccelerationTest/src/com/android/test/hwui/LinesActivity.java
index 6afbb01..91e3b84 100644
--- a/tests/HwAccelerationTest/src/com/android/test/hwui/LinesActivity.java
+++ b/tests/HwAccelerationTest/src/com/android/test/hwui/LinesActivity.java
@@ -35,7 +35,7 @@ public class LinesActivity extends Activity {
         setContentView(view);
     }
 
-    static class LinesView extends View {
+    public static class LinesView extends View {
         private static final boolean LINE_AA = false;
 
         private final Bitmap mBitmap1;
@@ -47,7 +47,7 @@ public class LinesActivity extends Activity {
         private final Paint mAlphaPaint;
         private final Paint mHairLinePaint;
 
-        LinesView(Context c) {
+        public LinesView(Context c) {
             super(c);
 
             mBitmap1 = BitmapFactory.decodeResource(c.getResources(), R.drawable.sunset1);
@@ -71,7 +71,7 @@ public class LinesActivity extends Activity {
             mAlphaPaint.setAntiAlias(LINE_AA);
             mAlphaPaint.setColor(0x7fff0050);
             mAlphaPaint.setStrokeWidth(10.0f);
-            
+
             mHairLinePaint = new Paint();
             mHairLinePaint.setAntiAlias(LINE_AA);
             mHairLinePaint.setColor(0xff0000ff);
@@ -99,11 +99,11 @@ public class LinesActivity extends Activity {
             canvas.drawLine(0.0f, 0.0f, 40.0f, 400.0f, mSmallPaint);
             canvas.drawLine(5.0f, 0.0f, 95.0f, 400.0f, mMediumPaint);
             canvas.drawLine(22.0f, 0.0f, 162.0f, 400.0f, mLargePaint);
-            
+
             mLargePaint.setShader(mShader);
             canvas.drawLine(42.0f, 0.0f, 222.0f, 400.0f, mLargePaint);
             mLargePaint.setShader(null);
-            
+
             canvas.drawLines(mPoints, mAlphaPaint);
 
             mSmallPaint.setAntiAlias(false);
@@ -111,14 +111,14 @@ public class LinesActivity extends Activity {
             mSmallPaint.setAntiAlias(LINE_AA);
             canvas.drawLine(0.0f, 0.0f, 0.0f, 400.0f, mSmallPaint);
             canvas.drawLine(0.0f, 400.0f, 400.0f, 400.0f, mSmallPaint);
-            
+
             canvas.translate(120.0f, 0.0f);
-            mAlphaPaint.setShader(mShader);            
+            mAlphaPaint.setShader(mShader);
             canvas.drawLines(mPoints, mAlphaPaint);
             mAlphaPaint.setShader(null);
 
             canvas.restore();
-            
+
             canvas.scale(10.0f, 10.0f);
             canvas.drawLine(50.0f, 40.0f, 10.0f, 40.0f, mSmallPaint);
             canvas.drawLine(10.0f, 50.0f, 50.0f, 50.0f, mSmallPaint);
diff --git a/tests/HwAccelerationTest/src/com/android/test/hwui/ShadersActivity.java b/tests/HwAccelerationTest/src/com/android/test/hwui/ShadersActivity.java
index f89e184..1d18f61 100644
--- a/tests/HwAccelerationTest/src/com/android/test/hwui/ShadersActivity.java
+++ b/tests/HwAccelerationTest/src/com/android/test/hwui/ShadersActivity.java
@@ -52,6 +52,9 @@ public class ShadersActivity extends Activity {
         private LinearGradient mDiagGradient;
         private LinearGradient mVertGradient;
         private Bitmap mTexture;
+        private Matrix mMtx1;
+        private Matrix mMtx2;
+        private Matrix mMtx3;
 
         public ShadersView(Context c) {
             super(c);
@@ -67,24 +70,24 @@ public class ShadersActivity extends Activity {
 
             mTranslatedShader = new BitmapShader(mTexture, Shader.TileMode.REPEAT,
                     Shader.TileMode.REPEAT);
-            Matrix m1 = new Matrix();
-            m1.setTranslate(mTexWidth / 2.0f, mTexHeight / 2.0f);
-            m1.postRotate(45, 0, 0);
-            mTranslatedShader.setLocalMatrix(m1);
+            mMtx1 = new Matrix();
+            mMtx1.setTranslate(mTexWidth / 2.0f, mTexHeight / 2.0f);
+            mMtx1.postRotate(45, 0, 0);
+            mTranslatedShader.setLocalMatrix(mMtx1);
 
             mScaledShader = new BitmapShader(mTexture, Shader.TileMode.MIRROR,
                     Shader.TileMode.MIRROR);
-            Matrix m2 = new Matrix();
-            m2.setScale(0.5f, 0.5f);
-            mScaledShader.setLocalMatrix(m2);
+            mMtx2 = new Matrix();
+            mMtx2.setScale(0.5f, 0.5f);
+            mScaledShader.setLocalMatrix(mMtx2);
 
             mHorGradient = new LinearGradient(0.0f, 0.0f, 1.0f, 0.0f,
                     Color.RED, Color.GREEN, Shader.TileMode.CLAMP);
-            Matrix m3 = new Matrix();
-            m3.setScale(mDrawHeight, 1.0f);
-            m3.postRotate(-90.0f);
-            m3.postTranslate(0.0f, mDrawHeight);
-            mHorGradient.setLocalMatrix(m3);
+            mMtx3 = new Matrix();
+            mMtx3.setScale(mDrawHeight, 1.0f);
+            mMtx3.postRotate(-90.0f);
+            mMtx3.postTranslate(0.0f, mDrawHeight);
+            mHorGradient.setLocalMatrix(mMtx3);
 
             mDiagGradient = new LinearGradient(0.0f, 0.0f, mDrawWidth / 1.5f, mDrawHeight,
                     Color.BLUE, Color.MAGENTA, Shader.TileMode.CLAMP);