Added asNewCustomStage to SkShader and implemented it for all the gradient shaders.

Not actually hooked up yet, but it should be ready to replace asABitmap for a future CL.
Review URL: https://codereview.appspot.com/6351113

git-svn-id: http://skia.googlecode.com/svn/trunk@4702 2bbb7eff-a529-9590-31e7-b0007b416f81

2 files changed, 73 insertions, 22 deletions

diff --git a/src/gpu/effects/GrGradientEffects.cpp b/src/gpu/effects/GrGradientEffects.cpp
index ec465b815b..2faeec02a1 100644
--- a/src/gpu/effects/GrGradientEffects.cpp
+++ b/src/gpu/effects/GrGradientEffects.cpp
@@ -8,6 +8,7 @@
 #include "GrGradientEffects.h"
 #include "gl/GrGLProgramStage.h"
 #include "GrProgramStageFactory.h"
+#include "SkGr.h"
 
 // Base class for GL gradient custom stages
 class GrGLGradientStage : public GrGLProgramStage {
@@ -50,10 +51,37 @@ GrGradientEffect::GrGradientEffect(GrTexture* texture)
     SkSafeRef(fTexture);
 }
 
+GrGradientEffect::GrGradientEffect(GrContext* ctx, const SkShader& shader)
+                                   : fTexture (NULL)
+                                   , fUseTexture (false) {
+    // TODO: check for simple cases where we don't need a texture:
+    //GradientInfo info;
+    //shader.asAGradient(&info);
+    //if (info.fColorCount == 2) { ...
+
+    SkBitmap bitmap;
+    shader.asABitmap(&bitmap, NULL, NULL, NULL);
+
+    // Note: we just construct a default sampler state here, which isn't great,
+    // however, as long as the bitmap has power-of-two dimensions, which should
+    // be the case for gradient bitmaps, it should be fine
+    GrAssert(SkIsPow2(bitmap.width()) && SkIsPow2(bitmap.height()));
+    GrSamplerState sampler;
+
+    GrContext::TextureCacheEntry entry = GrLockCachedBitmapTexture(ctx, bitmap,
+                                                                   &sampler);
+    fTexture = entry.texture();
+    SkSafeRef(fTexture);
+    fUseTexture = true;
+
+    // Unlock immediately, this is not great, but we don't have a way of
+    // knowing when else to unlock it currently, so it may get purged from
+    // the cache, but it'll still be ref'd until it's no longer being used.
+    GrUnlockCachedBitmapTexture(ctx, entry);
+}
+
 GrGradientEffect::~GrGradientEffect() {
-    if (fTexture) {
-        SkSafeUnref(fTexture);
-    }
+    SkSafeUnref(fTexture);
 }
 
 unsigned int GrGradientEffect::numTextures() const {
@@ -105,6 +133,10 @@ GrLinearGradient::GrLinearGradient(GrTexture* texture)
                   : INHERITED(texture) { 
 }
 
+GrLinearGradient::GrLinearGradient(GrContext* ctx, const SkShader& shader)
+                  : INHERITED(ctx, shader) {
+}
+
 GrLinearGradient::~GrLinearGradient() {
 
 }
@@ -113,10 +145,6 @@ const GrProgramStageFactory& GrLinearGradient::getFactory() const {
     return GrTProgramStageFactory<GrLinearGradient>::getInstance();
 }
 
-bool GrLinearGradient::isEqual(const GrCustomStage& sBase) const {
-    return INHERITED::isEqual(sBase);
-}
-
 /////////////////////////////////////////////////////////////////////
 
 class GrGLRadialGradient : public GrGLGradientStage {
@@ -160,19 +188,18 @@ GrRadialGradient::GrRadialGradient(GrTexture* texture)
 
 }
 
+GrRadialGradient::GrRadialGradient(GrContext* ctx, const SkShader& shader)
+    : INHERITED(ctx, shader) {
+}
+
 GrRadialGradient::~GrRadialGradient() {
 
 }
 
-
 const GrProgramStageFactory& GrRadialGradient::getFactory() const {
     return GrTProgramStageFactory<GrRadialGradient>::getInstance();
 }
 
-bool GrRadialGradient::isEqual(const GrCustomStage& sBase) const {
-    return INHERITED::isEqual(sBase);
-}
-
 /////////////////////////////////////////////////////////////////////
 
 // For brevity, and these definitions are likely to move to a different class soon.
@@ -418,6 +445,19 @@ GrRadial2Gradient::GrRadial2Gradient(GrTexture* texture,
 
 }
 
+GrRadial2Gradient::GrRadial2Gradient(GrContext* ctx, const SkShader& shader)
+    : INHERITED(ctx, shader) {
+    SkShader::GradientInfo info;
+    info.fColorCount = 0;
+    shader.asAGradient(&info);
+    fCenterX1 = SkPoint::Distance(info.fPoint[0], info.fPoint[1]);
+    SkScalar diffRadius = info.fRadius[1] - info.fRadius[0];
+    fPosRoot = diffRadius < 0;
+    SkScalar inv = 0 == diffRadius ? 0 : SkScalarInvert(diffRadius);
+    fRadius0 = SkScalarMul(info.fRadius[0], inv);
+    fCenterX1 = SkScalarMul(fCenterX1, inv);
+}
+
 GrRadial2Gradient::~GrRadial2Gradient() {
 
 }
@@ -736,6 +776,16 @@ GrConical2Gradient::GrConical2Gradient(GrTexture* texture,
 
 }
 
+GrConical2Gradient::GrConical2Gradient(GrContext* ctx, const SkShader& shader)
+    : INHERITED(ctx, shader) {
+    SkShader::GradientInfo info;
+    info.fColorCount = 0;
+    shader.asAGradient(&info);
+    fCenterX1 = SkPoint::Distance(info.fPoint[0], info.fPoint[1]);
+    fRadius0 = info.fRadius[0];
+    fDiffRadius = info.fRadius[1] - info.fRadius[0];
+}
+
 GrConical2Gradient::~GrConical2Gradient() {
 
 }
@@ -796,6 +846,10 @@ GrSweepGradient::GrSweepGradient(GrTexture* texture)
 
 }
 
+GrSweepGradient::GrSweepGradient(GrContext* ctx, const SkShader& shader) 
+    : INHERITED(ctx, shader) {
+}
+
 GrSweepGradient::~GrSweepGradient() {
 
 }
@@ -804,7 +858,3 @@ const GrProgramStageFactory& GrSweepGradient::getFactory() const {
     return GrTProgramStageFactory<GrSweepGradient>::getInstance();
 }
 
-bool GrSweepGradient::isEqual(const GrCustomStage& sBase) const {
-    return INHERITED::isEqual(sBase);
-}
-
diff --git a/src/gpu/effects/GrGradientEffects.h b/src/gpu/effects/GrGradientEffects.h
index eb1a8f2739..fdd5d52353 100644
--- a/src/gpu/effects/GrGradientEffects.h
+++ b/src/gpu/effects/GrGradientEffects.h
@@ -11,6 +11,7 @@
 #include "GrSingleTextureEffect.h"
 #include "GrTypes.h"
 #include "GrScalar.h"
+#include "SkShader.h"
 
 /*
  * The intepretation of the texture matrix depends on the sample mode. The
@@ -40,9 +41,7 @@ class GrGradientEffect : public GrCustomStage {
 public:
 
     GrGradientEffect(GrTexture* texture);
-    
-    // TODO: Look at a GradientInfo and make the texture only if necessary
-    // GrGradientEffect(GrContext* ctx, GradientInfo* info);
+    GrGradientEffect(GrContext* ctx, const SkShader& shader);
 
     virtual ~GrGradientEffect();
 
@@ -67,11 +66,11 @@ class GrLinearGradient : public GrGradientEffect {
 public:
 
     GrLinearGradient(GrTexture* texture);
+    GrLinearGradient(GrContext* ctx, const SkShader& shader);
     virtual ~GrLinearGradient();
 
     static const char* Name() { return "Linear Gradient"; }
     virtual const GrProgramStageFactory& getFactory() const SK_OVERRIDE;
-    virtual bool isEqual(const GrCustomStage&) const SK_OVERRIDE;
 
     typedef GrGLLinearGradient GLProgramStage;
 
@@ -87,11 +86,11 @@ class GrRadialGradient : public GrGradientEffect {
 public:
 
     GrRadialGradient(GrTexture* texture);
+    GrRadialGradient(GrContext* ctx, const SkShader& shader);
     virtual ~GrRadialGradient();
 
     static const char* Name() { return "Radial Gradient"; }
     virtual const GrProgramStageFactory& getFactory() const SK_OVERRIDE;
-    virtual bool isEqual(const GrCustomStage&) const SK_OVERRIDE;
 
     typedef GrGLRadialGradient GLProgramStage;
 
@@ -107,6 +106,7 @@ class GrRadial2Gradient : public GrGradientEffect {
 public:
 
     GrRadial2Gradient(GrTexture* texture, GrScalar center, GrScalar radius, bool posRoot);
+    GrRadial2Gradient(GrContext* ctx, const SkShader& shader);
     virtual ~GrRadial2Gradient();
 
     static const char* Name() { return "Two-Point Radial Gradient"; }
@@ -143,6 +143,7 @@ class GrConical2Gradient : public GrGradientEffect {
 public:
 
     GrConical2Gradient(GrTexture* texture, GrScalar center, GrScalar radius, GrScalar diffRadius);
+    GrConical2Gradient(GrContext* ctx, const SkShader& shader);
     virtual ~GrConical2Gradient();
 
     static const char* Name() { return "Two-Point Conical Gradient"; }
@@ -179,11 +180,11 @@ class GrSweepGradient : public GrGradientEffect {
 public:
 
     GrSweepGradient(GrTexture* texture);
+    GrSweepGradient(GrContext* ctx, const SkShader& shader);
     virtual ~GrSweepGradient();
 
     static const char* Name() { return "Sweep Gradient"; }
     virtual const GrProgramStageFactory& getFactory() const SK_OVERRIDE;
-    virtual bool isEqual(const GrCustomStage&) const SK_OVERRIDE;
 
     typedef GrGLSweepGradient GLProgramStage;