Early rejection on shadows which are outside of the clip bound.
All the computations are estimated using bounding box.
TODO: Spot shadow could have more accurate but also more expensive methods, we need
more experiments to decide.
Change-Id: I9c10c419576cee55daf0f9f278b0db78cb847447
diff --git a/libs/hwui/OpenGLRenderer.cpp b/libs/hwui/OpenGLRenderer.cpp
index cb8155b..cdd789d 100644
--- a/libs/hwui/OpenGLRenderer.cpp
+++ b/libs/hwui/OpenGLRenderer.cpp
@@ -3226,11 +3226,13 @@
const int casterVertexCount = casterVertices2d.size();
Vector3 casterPolygon[casterVertexCount];
float minZ = FLT_MAX;
+ float maxZ = -FLT_MAX;
for (int i = 0; i < casterVertexCount; i++) {
const Vertex& point2d = casterVertices2d[i];
casterPolygon[i] = Vector3(point2d.x, point2d.y, 0);
mapPointFakeZ(casterPolygon[i], casterTransformXY, casterTransformZ);
minZ = fmin(minZ, casterPolygon[i].z);
+ maxZ = fmax(maxZ, casterPolygon[i].z);
}
// map the centroid of the caster into 3d
@@ -3248,6 +3250,15 @@
}
centroid3d.z += casterLift;
}
+
+ // Check whether we want to draw the shadow at all by checking the caster's
+ // bounds against clip.
+ // We only have ortho projection, so we can just ignore the Z in caster for
+ // simple rejection calculation.
+ Rect localClip = mSnapshot->getLocalClip();
+ Rect casterBounds(casterOutline->getBounds());
+ casterTransformXY.mapRect(casterBounds);
+
bool isCasterOpaque = (casterAlpha == 1.0f);
// draw caster's shadows
if (mCaches.propertyAmbientShadowStrength > 0) {
@@ -3255,7 +3266,7 @@
VertexBuffer ambientShadowVertexBuffer;
VertexBufferMode vertexBufferMode = ShadowTessellator::tessellateAmbientShadow(
isCasterOpaque, casterPolygon, casterVertexCount, centroid3d,
- ambientShadowVertexBuffer);
+ casterBounds, localClip, maxZ, ambientShadowVertexBuffer);
drawVertexBuffer(vertexBufferMode, ambientShadowVertexBuffer, &paint);
}
@@ -3266,7 +3277,8 @@
mCaches.propertyLightPosYScale, mCaches.propertyLightPosZScale);
VertexBufferMode vertexBufferMode = ShadowTessellator::tessellateSpotShadow(
isCasterOpaque, casterPolygon, casterVertexCount, lightPosScale,
- *currentTransform(), getWidth(), getHeight(), spotShadowVertexBuffer);
+ *currentTransform(), getWidth(), getHeight(), casterBounds, localClip,
+ spotShadowVertexBuffer);
drawVertexBuffer(vertexBufferMode, spotShadowVertexBuffer, &paint);
}
diff --git a/libs/hwui/Rect.h b/libs/hwui/Rect.h
index c230149..0083b77 100644
--- a/libs/hwui/Rect.h
+++ b/libs/hwui/Rect.h
@@ -18,6 +18,7 @@
#define ANDROID_HWUI_RECT_H
#include <cmath>
+#include <SkRect.h>
#include <utils/Log.h>
@@ -68,6 +69,13 @@
bottom(height) {
}
+ inline Rect(const SkRect& rect):
+ left(rect.fLeft),
+ top(rect.fTop),
+ right(rect.fRight),
+ bottom(rect.fBottom) {
+ }
+
friend int operator==(const Rect& a, const Rect& b) {
return !memcmp(&a, &b, sizeof(a));
}
diff --git a/libs/hwui/ShadowTessellator.cpp b/libs/hwui/ShadowTessellator.cpp
index 771904a..4d0edfb 100644
--- a/libs/hwui/ShadowTessellator.cpp
+++ b/libs/hwui/ShadowTessellator.cpp
@@ -35,7 +35,8 @@
VertexBufferMode ShadowTessellator::tessellateAmbientShadow(bool isCasterOpaque,
const Vector3* casterPolygon, int casterVertexCount,
- const Vector3& centroid3d, VertexBuffer& shadowVertexBuffer) {
+ const Vector3& centroid3d, const Rect& casterBounds,
+ const Rect& localClip, float maxZ, VertexBuffer& shadowVertexBuffer) {
ATRACE_CALL();
// A bunch of parameters to tweak the shadow.
@@ -43,6 +44,16 @@
const float heightFactor = 1.0f / 128;
const float geomFactor = 64;
+ Rect ambientShadowBounds(casterBounds);
+ ambientShadowBounds.outset(maxZ * geomFactor * heightFactor);
+
+ if (!localClip.intersects(ambientShadowBounds)) {
+#if DEBUG_SHADOW
+ ALOGD("Ambient shadow is out of clip rect!");
+#endif
+ return kVertexBufferMode_OnePolyRingShadow;
+ }
+
return AmbientShadow::createAmbientShadow(isCasterOpaque, casterPolygon,
casterVertexCount, centroid3d, heightFactor, geomFactor,
shadowVertexBuffer);
@@ -52,7 +63,8 @@
VertexBufferMode ShadowTessellator::tessellateSpotShadow(bool isCasterOpaque,
const Vector3* casterPolygon, int casterVertexCount,
const Vector3& lightPosScale, const mat4& receiverTransform,
- int screenWidth, int screenHeight, VertexBuffer& shadowVertexBuffer) {
+ int screenWidth, int screenHeight, const Rect& casterBounds,
+ const Rect& localClip, VertexBuffer& shadowVertexBuffer) {
ATRACE_CALL();
// A bunch of parameters to tweak the shadow.
@@ -73,6 +85,18 @@
const float lightSize = maximal / 4;
const int lightVertexCount = 8;
+ // Now light and caster are both in local space, we will check whether
+ // the shadow is within the clip area.
+ Rect lightRect = Rect(lightCenter.x - lightSize, lightCenter.y - lightSize,
+ lightCenter.x + lightSize, lightCenter.y + lightSize);
+ lightRect.unionWith(localClip);
+ if (!lightRect.intersects(casterBounds)) {
+#if DEBUG_SHADOW
+ ALOGD("Spot shadow is out of clip rect!");
+#endif
+ return kVertexBufferMode_OnePolyRingShadow;
+ }
+
VertexBufferMode mode = SpotShadow::createSpotShadow(isCasterOpaque,
casterPolygon, casterVertexCount, lightCenter, lightSize,
lightVertexCount, shadowVertexBuffer);
diff --git a/libs/hwui/ShadowTessellator.h b/libs/hwui/ShadowTessellator.h
index ab039fa..ff3de74 100644
--- a/libs/hwui/ShadowTessellator.h
+++ b/libs/hwui/ShadowTessellator.h
@@ -66,12 +66,14 @@
public:
static VertexBufferMode tessellateAmbientShadow(bool isCasterOpaque,
const Vector3* casterPolygon, int casterVertexCount,
- const Vector3& centroid3d, VertexBuffer& shadowVertexBuffer);
+ const Vector3& centroid3d, const Rect& casterBounds,
+ const Rect& localClip, float maxZ, VertexBuffer& shadowVertexBuffer);
static VertexBufferMode tessellateSpotShadow(bool isCasterOpaque,
const Vector3* casterPolygon, int casterVertexCount,
const Vector3& lightPosScale, const mat4& receiverTransform,
- int screenWidth, int screenHeight, VertexBuffer& shadowVertexBuffer);
+ int screenWidth, int screenHeight, const Rect& casterBounds,
+ const Rect& localClip, VertexBuffer& shadowVertexBuffer);
static void generateShadowIndices(uint16_t* shadowIndices);