Preliminary support for clipRect(Rect, Op)
This adds basic support for clip regions. It is currently disabled at compile
time. Enabling clip regions will require setting up a stencil buffer.
Change-Id: I638616a972276e38737f8ac0633692c3845eaa74
diff --git a/libs/hwui/Snapshot.cpp b/libs/hwui/Snapshot.cpp
index a85362d..5f801fb 100644
--- a/libs/hwui/Snapshot.cpp
+++ b/libs/hwui/Snapshot.cpp
@@ -31,6 +31,7 @@
transform = &mTransformRoot;
clipRect = &mClipRectRoot;
region = NULL;
+ clipRegion = NULL;
}
/**
@@ -52,8 +53,21 @@
if (saveFlags & SkCanvas::kClip_SaveFlag) {
mClipRectRoot.set(*s->clipRect);
clipRect = &mClipRectRoot;
+#if STENCIL_BUFFER_SIZE
+ if (s->clipRegion) {
+ mClipRegionRoot.merge(*s->clipRegion);
+ clipRegion = &mClipRegionRoot;
+ } else {
+ clipRegion = NULL;
+ }
+#else
+ clipRegion = NULL;
+#endif
} else {
clipRect = s->clipRect;
+#if STENCIL_BUFFER_SIZE
+ clipRegion = s->clipRegion;
+#endif
}
if (s->flags & Snapshot::kFlagFboTarget) {
@@ -68,6 +82,77 @@
// Clipping
///////////////////////////////////////////////////////////////////////////////
+void Snapshot::ensureClipRegion() {
+#if STENCIL_BUFFER_SIZE
+ if (!clipRegion) {
+ clipRegion = &mClipRegionRoot;
+ android::Rect tmp(clipRect->left, clipRect->top, clipRect->right, clipRect->bottom);
+ clipRegion->set(tmp);
+ }
+#endif
+}
+
+void Snapshot::copyClipRectFromRegion() {
+#if STENCIL_BUFFER_SIZE
+ if (!clipRegion->isEmpty()) {
+ android::Rect bounds(clipRegion->bounds());
+ clipRect->set(bounds.left, bounds.top, bounds.right, bounds.bottom);
+
+ if (clipRegion->isRect()) {
+ clipRegion->clear();
+ clipRegion = NULL;
+ }
+ } else {
+ clipRect->setEmpty();
+ clipRegion = NULL;
+ }
+#endif
+}
+
+bool Snapshot::clipRegionOr(float left, float top, float right, float bottom) {
+#if STENCIL_BUFFER_SIZE
+ android::Rect tmp(left, top, right, bottom);
+ clipRegion->orSelf(tmp);
+ copyClipRectFromRegion();
+ return true;
+#else
+ return false;
+#endif
+}
+
+bool Snapshot::clipRegionXor(float left, float top, float right, float bottom) {
+#if STENCIL_BUFFER_SIZE
+ android::Rect tmp(left, top, right, bottom);
+ clipRegion->xorSelf(tmp);
+ copyClipRectFromRegion();
+ return true;
+#else
+ return false;
+#endif
+}
+
+bool Snapshot::clipRegionAnd(float left, float top, float right, float bottom) {
+#if STENCIL_BUFFER_SIZE
+ android::Rect tmp(left, top, right, bottom);
+ clipRegion->andSelf(tmp);
+ copyClipRectFromRegion();
+ return true;
+#else
+ return false;
+#endif
+}
+
+bool Snapshot::clipRegionNand(float left, float top, float right, float bottom) {
+#if STENCIL_BUFFER_SIZE
+ android::Rect tmp(left, top, right, bottom);
+ clipRegion->subtractSelf(tmp);
+ copyClipRectFromRegion();
+ return true;
+#else
+ return false;
+#endif
+}
+
bool Snapshot::clip(float left, float top, float right, float bottom, SkRegion::Op op) {
Rect r(left, top, right, bottom);
transform->mapRect(r);
@@ -77,32 +162,46 @@
bool Snapshot::clipTransformed(const Rect& r, SkRegion::Op op) {
bool clipped = false;
- // NOTE: The unimplemented operations require support for regions
- // Supporting regions would require using a stencil buffer instead
- // of the scissor. The stencil buffer itself is not too expensive
- // (memory cost excluded) but on fillrate limited devices, managing
- // the stencil might have a negative impact on the framerate.
switch (op) {
- case SkRegion::kDifference_Op:
+ case SkRegion::kDifference_Op: {
+ ensureClipRegion();
+ clipped = clipRegionNand(r.left, r.top, r.right, r.bottom);
break;
- case SkRegion::kIntersect_Op:
- clipped = clipRect->intersect(r);
- if (!clipped) {
- clipRect->setEmpty();
- clipped = true;
+ }
+ case SkRegion::kIntersect_Op: {
+ if (CC_UNLIKELY(clipRegion)) {
+ clipped = clipRegionOr(r.left, r.top, r.right, r.bottom);
+ } else {
+ clipped = clipRect->intersect(r);
+ if (!clipped) {
+ clipRect->setEmpty();
+ clipped = true;
+ }
}
break;
- case SkRegion::kUnion_Op:
- clipped = clipRect->unionWith(r);
+ }
+ case SkRegion::kUnion_Op: {
+ if (CC_UNLIKELY(clipRegion)) {
+ clipped = clipRegionAnd(r.left, r.top, r.right, r.bottom);
+ } else {
+ clipped = clipRect->unionWith(r);
+ }
break;
- case SkRegion::kXOR_Op:
+ }
+ case SkRegion::kXOR_Op: {
+ ensureClipRegion();
+ clipped = clipRegionXor(r.left, r.top, r.right, r.bottom);
break;
- case SkRegion::kReverseDifference_Op:
+ }
+ case SkRegion::kReverseDifference_Op: {
+ // TODO!!!!!!!
break;
- case SkRegion::kReplace_Op:
- clipRect->set(r);
+ }
+ case SkRegion::kReplace_Op: {
+ setClip(r.left, r.top, r.right, r.bottom);
clipped = true;
break;
+ }
}
if (clipped) {
@@ -114,6 +213,10 @@
void Snapshot::setClip(float left, float top, float right, float bottom) {
clipRect->set(left, top, right, bottom);
+ if (clipRegion) {
+ clipRegion->clear();
+ clipRegion = NULL;
+ }
flags |= Snapshot::kFlagClipSet;
}
@@ -129,8 +232,7 @@
void Snapshot::resetClip(float left, float top, float right, float bottom) {
clipRect = &mClipRectRoot;
- clipRect->set(left, top, right, bottom);
- flags |= Snapshot::kFlagClipSet;
+ setClip(left, top, right, bottom);
}
///////////////////////////////////////////////////////////////////////////////
diff --git a/libs/hwui/Snapshot.h b/libs/hwui/Snapshot.h
index c94af7e..b2bc879 100644
--- a/libs/hwui/Snapshot.h
+++ b/libs/hwui/Snapshot.h
@@ -181,7 +181,7 @@
mat4* transform;
/**
- * Current clip region. The clip is stored in canvas-space coordinates,
+ * Current clip rect. The clip is stored in canvas-space coordinates,
* (screen-space coordinates in the regular case.)
*
* This is a reference to a rect owned by this snapshot or another
@@ -190,6 +190,17 @@
Rect* clipRect;
/**
+ * Current clip region. The clip is stored in canvas-space coordinates,
+ * (screen-space coordinates in the regular case.)
+ *
+ * This is a reference to a region owned by this snapshot or another
+ * snapshot. This pointer must not be freed. See ::mClipRegionRoot.
+ *
+ * This field is used only if STENCIL_BUFFER_SIZE is > 0.
+ */
+ Region* clipRegion;
+
+ /**
* The ancestor layer's dirty region.
*
* This is a reference to a region owned by a layer. This pointer must
@@ -198,10 +209,22 @@
Region* region;
private:
+ void ensureClipRegion();
+ void copyClipRectFromRegion();
+
+ bool clipRegionOr(float left, float top, float right, float bottom);
+ bool clipRegionXor(float left, float top, float right, float bottom);
+ bool clipRegionAnd(float left, float top, float right, float bottom);
+ bool clipRegionNand(float left, float top, float right, float bottom);
+
mat4 mTransformRoot;
Rect mClipRectRoot;
Rect mLocalClip;
+#if STENCIL_BUFFER_SIZE
+ Region mClipRegionRoot;
+#endif
+
}; // class Snapshot
}; // namespace uirenderer