Switch to cos interpolation of shadow alpha
bug:16852257
Updates default shadow opacities to compensate.
Also, update variable/constant naming related to vertex alpha.
Change-Id: I9055b4ac3c9ac305ca9d515f21b52d6aa6dc9c5c
diff --git a/core/res/res/values/styles.xml b/core/res/res/values/styles.xml
index 35baf9c..8fc9bac 100644
--- a/core/res/res/values/styles.xml
+++ b/core/res/res/values/styles.xml
@@ -1360,7 +1360,7 @@
<item name="lightZ">800dp</item>
<item name="lightRadius">800dp</item>
<item name="ambientShadowAlpha">0.06</item>
- <item name="spotShadowAlpha">0.22</item>
+ <item name="spotShadowAlpha">0.16</item>
</style>
</resources>
diff --git a/libs/hwui/AmbientShadow.cpp b/libs/hwui/AmbientShadow.cpp
index 181230a..9cc83ed 100644
--- a/libs/hwui/AmbientShadow.cpp
+++ b/libs/hwui/AmbientShadow.cpp
@@ -117,10 +117,13 @@
// inner ring of points
float opacity = 1.0 / (1 + rayHeight[rayIndex] * heightFactor);
+ // NOTE: Shadow alpha values are transformed when stored in alphavertices,
+ // so that they can be consumed directly by gFS_Main_ApplyVertexAlphaShadowInterp
+ float transformedOpacity = acos(1.0f - 2.0f * opacity);
AlphaVertex::set(&shadowVertices[rays + rayIndex],
intersection.x,
intersection.y,
- opacity);
+ transformedOpacity);
}
if (isCasterOpaque) {
diff --git a/libs/hwui/OpenGLRenderer.cpp b/libs/hwui/OpenGLRenderer.cpp
index 7123bfe..d1522b6 100755
--- a/libs/hwui/OpenGLRenderer.cpp
+++ b/libs/hwui/OpenGLRenderer.cpp
@@ -1641,9 +1641,9 @@
mCaches.disableTexCoordsVertexArray();
}
-void OpenGLRenderer::setupDrawAA(bool useShadowInterp) {
- mDescription.isAA = true;
- mDescription.isShadowAA = useShadowInterp;
+void OpenGLRenderer::setupDrawVertexAlpha(bool useShadowAlphaInterp) {
+ mDescription.hasVertexAlpha = true;
+ mDescription.useShadowAlphaInterp = useShadowAlphaInterp;
}
void OpenGLRenderer::setupDrawColor(int color, int alpha) {
@@ -2382,7 +2382,7 @@
setupDraw();
setupDrawNoTexture();
- if (isAA) setupDrawAA((displayFlags & kVertexBuffer_ShadowAA));
+ if (isAA) setupDrawVertexAlpha((displayFlags & kVertexBuffer_ShadowInterp));
setupDrawColor(color, ((color >> 24) & 0xFF) * mSnapshot->alpha);
setupDrawColorFilter(getColorFilter(paint));
setupDrawShader(getShader(paint));
@@ -3168,12 +3168,12 @@
if (ambientShadowVertexBuffer && mAmbientShadowAlpha > 0) {
paint.setARGB(casterAlpha * mAmbientShadowAlpha, 0, 0, 0);
- drawVertexBuffer(*ambientShadowVertexBuffer, &paint, kVertexBuffer_ShadowAA);
+ drawVertexBuffer(*ambientShadowVertexBuffer, &paint, kVertexBuffer_ShadowInterp);
}
if (spotShadowVertexBuffer && mSpotShadowAlpha > 0) {
paint.setARGB(casterAlpha * mSpotShadowAlpha, 0, 0, 0);
- drawVertexBuffer(*spotShadowVertexBuffer, &paint, kVertexBuffer_ShadowAA);
+ drawVertexBuffer(*spotShadowVertexBuffer, &paint, kVertexBuffer_ShadowInterp);
}
return DrawGlInfo::kStatusDrew;
diff --git a/libs/hwui/OpenGLRenderer.h b/libs/hwui/OpenGLRenderer.h
index 2a9badd..fc95c18 100755
--- a/libs/hwui/OpenGLRenderer.h
+++ b/libs/hwui/OpenGLRenderer.h
@@ -96,7 +96,7 @@
enum VertexBufferDisplayFlags {
kVertexBuffer_Offset = 0x1,
- kVertexBuffer_ShadowAA = 0x2,
+ kVertexBuffer_ShadowInterp = 0x2,
};
/**
@@ -847,7 +847,7 @@
void setupDrawWithTextureAndColor(bool isAlpha8 = false);
void setupDrawWithExternalTexture();
void setupDrawNoTexture();
- void setupDrawAA(bool useShadowInterp);
+ void setupDrawVertexAlpha(bool useShadowAlphaInterp);
void setupDrawColor(int color, int alpha);
void setupDrawColor(float r, float g, float b, float a);
void setupDrawAlpha8Color(int color, int alpha);
diff --git a/libs/hwui/Program.h b/libs/hwui/Program.h
index 1d95c40..56773f4 100644
--- a/libs/hwui/Program.h
+++ b/libs/hwui/Program.h
@@ -71,8 +71,8 @@
#define PROGRAM_GRADIENT_TYPE_SHIFT 33 // 2 bits for gradient type
#define PROGRAM_MODULATE_SHIFT 35
-#define PROGRAM_HAS_AA_SHIFT 36
-#define PROGRAM_HAS_SHADOW_AA_SHIFT 37
+#define PROGRAM_HAS_VERTEX_ALPHA_SHIFT 36
+#define PROGRAM_USE_SHADOW_ALPHA_INTERP_SHIFT 37
#define PROGRAM_HAS_EXTERNAL_TEXTURE_SHIFT 38
#define PROGRAM_HAS_TEXTURE_TRANSFORM_SHIFT 39
@@ -135,8 +135,8 @@
bool hasBitmap;
bool isBitmapNpot;
- bool isAA; // drawing with a per-vertex alpha
- bool isShadowAA; // drawing per vertex alpha with shadow interpolation
+ bool hasVertexAlpha;
+ bool useShadowAlphaInterp;
bool hasGradient;
Gradient gradientType;
@@ -176,8 +176,8 @@
hasColors = false;
- isAA = false;
- isShadowAA = false;
+ hasVertexAlpha = false;
+ useShadowAlphaInterp = false;
modulate = false;
@@ -264,8 +264,8 @@
key |= (framebufferMode & PROGRAM_MAX_XFERMODE) << PROGRAM_XFERMODE_FRAMEBUFFER_SHIFT;
if (swapSrcDst) key |= PROGRAM_KEY_SWAP_SRC_DST;
if (modulate) key |= programid(0x1) << PROGRAM_MODULATE_SHIFT;
- if (isAA) key |= programid(0x1) << PROGRAM_HAS_AA_SHIFT;
- if (isShadowAA) key |= programid(0x1) << PROGRAM_HAS_SHADOW_AA_SHIFT;
+ if (hasVertexAlpha) key |= programid(0x1) << PROGRAM_HAS_VERTEX_ALPHA_SHIFT;
+ if (useShadowAlphaInterp) key |= programid(0x1) << PROGRAM_USE_SHADOW_ALPHA_INTERP_SHIFT;
if (hasExternalTexture) key |= programid(0x1) << PROGRAM_HAS_EXTERNAL_TEXTURE_SHIFT;
if (hasTextureTransform) key |= programid(0x1) << PROGRAM_HAS_TEXTURE_TRANSFORM_SHIFT;
if (hasGammaCorrection) key |= programid(0x1) << PROGRAM_HAS_GAMMA_CORRECTION;
diff --git a/libs/hwui/ProgramCache.cpp b/libs/hwui/ProgramCache.cpp
index 2dd89b8..c802b18 100644
--- a/libs/hwui/ProgramCache.cpp
+++ b/libs/hwui/ProgramCache.cpp
@@ -46,7 +46,7 @@
"attribute vec2 texCoords;\n";
const char* gVS_Header_Attributes_Colors =
"attribute vec4 colors;\n";
-const char* gVS_Header_Attributes_AAVertexShapeParameters =
+const char* gVS_Header_Attributes_VertexAlphaParameters =
"attribute float vtxAlpha;\n";
const char* gVS_Header_Uniforms_TextureTransform =
"uniform mat4 mainTextureTransform;\n";
@@ -64,7 +64,7 @@
"varying vec2 outTexCoords;\n";
const char* gVS_Header_Varyings_HasColors =
"varying vec4 outColors;\n";
-const char* gVS_Header_Varyings_IsAAVertexShape =
+const char* gVS_Header_Varyings_HasVertexAlpha =
"varying float alpha;\n";
const char* gVS_Header_Varyings_HasBitmap =
"varying highp vec2 outBitmapTexCoords;\n";
@@ -122,9 +122,7 @@
" vec4 transformedPosition = projection * transform * position;\n"
" gl_Position = transformedPosition;\n";
-const char* gVS_Main_ShadowAAVertexShape =
- " alpha = pow(vtxAlpha, 0.667);\n";
-const char* gVS_Main_AAVertexShape =
+const char* gVS_Main_VertexAlpha =
" alpha = vtxAlpha;\n";
const char* gVS_Main_HasRoundRectClip =
@@ -239,10 +237,10 @@
" fragColor = color;\n";
const char* gFS_Main_ModulateColor =
" fragColor *= color.a;\n";
-const char* gFS_Main_AccountForAAVertexShape =
+const char* gFS_Main_ApplyVertexAlphaLinearInterp =
" fragColor *= alpha;\n";
-const char* gFS_Main_AccountForShadowAAVertexShape =
- " fragColor *= pow(alpha, 1.5);\n";
+const char* gFS_Main_ApplyVertexAlphaShadowInterp =
+ " fragColor *= (1.0 - cos(alpha)) / 2.0;\n";
const char* gFS_Main_FetchTexture[2] = {
// Don't modulate
@@ -473,8 +471,8 @@
if (description.hasTexture || description.hasExternalTexture) {
shader.append(gVS_Header_Attributes_TexCoords);
}
- if (description.isAA) {
- shader.append(gVS_Header_Attributes_AAVertexShapeParameters);
+ if (description.hasVertexAlpha) {
+ shader.append(gVS_Header_Attributes_VertexAlphaParameters);
}
if (description.hasColors) {
shader.append(gVS_Header_Attributes_Colors);
@@ -497,8 +495,8 @@
if (description.hasTexture || description.hasExternalTexture) {
shader.append(gVS_Header_Varyings_HasTexture);
}
- if (description.isAA) {
- shader.append(gVS_Header_Varyings_IsAAVertexShape);
+ if (description.hasVertexAlpha) {
+ shader.append(gVS_Header_Varyings_HasVertexAlpha);
}
if (description.hasColors) {
shader.append(gVS_Header_Varyings_HasColors);
@@ -520,12 +518,8 @@
} else if (description.hasTexture || description.hasExternalTexture) {
shader.append(gVS_Main_OutTexCoords);
}
- if (description.isAA) {
- if (description.isShadowAA) {
- shader.append(gVS_Main_ShadowAAVertexShape);
- } else {
- shader.append(gVS_Main_AAVertexShape);
- }
+ if (description.hasVertexAlpha) {
+ shader.append(gVS_Main_VertexAlpha);
}
if (description.hasColors) {
shader.append(gVS_Main_OutColors);
@@ -575,8 +569,8 @@
if (description.hasTexture || description.hasExternalTexture) {
shader.append(gVS_Header_Varyings_HasTexture);
}
- if (description.isAA) {
- shader.append(gVS_Header_Varyings_IsAAVertexShape);
+ if (description.hasVertexAlpha) {
+ shader.append(gVS_Header_Varyings_HasVertexAlpha);
}
if (description.hasColors) {
shader.append(gVS_Header_Varyings_HasColors);
@@ -617,7 +611,7 @@
}
// Optimization for common cases
- if (!description.isAA
+ if (!description.hasVertexAlpha
&& !blendFramebuffer
&& !description.hasColors
&& description.colorOp == ProgramDescription::kColorNone
@@ -759,11 +753,11 @@
// Apply the color op if needed
shader.append(gFS_Main_ApplyColorOp[description.colorOp]);
- if (description.isAA) {
- if (description.isShadowAA) {
- shader.append(gFS_Main_AccountForShadowAAVertexShape);
+ if (description.hasVertexAlpha) {
+ if (description.useShadowAlphaInterp) {
+ shader.append(gFS_Main_ApplyVertexAlphaShadowInterp);
} else {
- shader.append(gFS_Main_AccountForAAVertexShape);
+ shader.append(gFS_Main_ApplyVertexAlphaLinearInterp);
}
}
diff --git a/libs/hwui/SpotShadow.cpp b/libs/hwui/SpotShadow.cpp
index 8c3077b..d726538 100644
--- a/libs/hwui/SpotShadow.cpp
+++ b/libs/hwui/SpotShadow.cpp
@@ -754,9 +754,13 @@
AlphaVertex* shadowVertices =
shadowTriangleStrip.alloc<AlphaVertex>(SHADOW_VERTEX_COUNT);
+ // NOTE: Shadow alpha values are transformed when stored in alphavertices,
+ // so that they can be consumed directly by gFS_Main_ApplyVertexAlphaShadowInterp
+ float transformedMaxAlpha = M_PI;
+
// Calculate the vertices (x, y, alpha) in the shadow area.
AlphaVertex centroidXYA;
- AlphaVertex::set(¢roidXYA, centroid.x, centroid.y, 1.0f);
+ AlphaVertex::set(¢roidXYA, centroid.x, centroid.y, transformedMaxAlpha);
for (int rayIndex = 0; rayIndex < rays; rayIndex++) {
float dx = cosf(step * rayIndex);
float dy = sinf(step * rayIndex);
@@ -770,14 +774,16 @@
// umbra ring
float umbraDistance = umbraDistPerRay[rayIndex];
AlphaVertex::set(&shadowVertices[rays + rayIndex],
- dx * umbraDistance + centroid.x, dy * umbraDistance + centroid.y, 1.0f);
+ dx * umbraDistance + centroid.x,
+ dy * umbraDistance + centroid.y,
+ transformedMaxAlpha);
// occluded umbra ring
if (hasOccludedUmbraArea) {
float occludedUmbraDistance = occludedUmbraDistPerRay[rayIndex];
AlphaVertex::set(&shadowVertices[2 * rays + rayIndex],
dx * occludedUmbraDistance + centroid.x,
- dy * occludedUmbraDistance + centroid.y, 1.0f);
+ dy * occludedUmbraDistance + centroid.y, transformedMaxAlpha);
} else {
// Put all vertices of the occluded umbra ring at the centroid.
shadowVertices[2 * rays + rayIndex] = centroidXYA;