Culling API
*** SKP format breaking change ***
Adding a couple of culling primitives: pushCull(SkRect) & popCull().
These are currently only plumbed for SKP playback quickreject.
At record time, we perform a couple of optimizations to trim down the
number of redundant culls:
* collapse empty pushCull/popCull pairs
* skip pushCull/popCull pairs nested within an identical cull rect
Things still missing/to consider:
* use an inlineable, simplified quickreject (Mike's old prototype)
* debugger visualization for cull boxes
* BBH integration: the initial prototype had some minimal BBH support,
but since the optimizations required expensive rewinds and culling
is expected to be a BBH alternative, it got dropped.
R=bsalomon@google.com, reed@google.com, robertphillips@google.com, caryclark@google.com, tomhudson@google.com, iancottrell@google.com
Author: fmalita@chromium.org
Review URL: https://codereview.chromium.org/138013009
git-svn-id: http://skia.googlecode.com/svn/trunk@13611 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/core/SkPictureRecord.cpp b/src/core/SkPictureRecord.cpp
index be86951..978e2b3 100644
--- a/src/core/SkPictureRecord.cpp
+++ b/src/core/SkPictureRecord.cpp
@@ -112,6 +112,8 @@
0, // COMMENT - no paint
0, // END_GROUP - no paint
1, // DRAWDRRECT - right after op code
+ 0, // PUSH_CULL - no paint
+ 0, // POP_CULL - no paint
};
SK_COMPILE_ASSERT(sizeof(gPaintOffsets) == LAST_DRAWTYPE_ENUM + 1,
@@ -220,6 +222,15 @@
}
/*
+ * Read the op code from 'offset' in 'writer'.
+ */
+#ifdef SK_DEBUG
+static DrawType peek_op(SkWriter32* writer, int32_t offset) {
+ return (DrawType)(writer->readTAt<uint32_t>(offset) >> 24);
+}
+#endif
+
+/*
* Read the op code from 'offset' in 'writer' and extract the size too.
*/
static DrawType peek_op_and_size(SkWriter32* writer, int32_t offset, uint32_t* size) {
@@ -1548,6 +1559,61 @@
this->validate(initialOffset, size);
}
+// [op/size] [rect] [skip offset]
+static const uint32_t kPushCullOpSize = 2 * kUInt32Size + sizeof(SkRect);
+void SkPictureRecord::onPushCull(const SkRect& cullRect) {
+ // Skip identical cull rects.
+ if (!fCullOffsetStack.isEmpty()) {
+ const SkRect& prevCull = fWriter.readTAt<SkRect>(fCullOffsetStack.top() - sizeof(SkRect));
+ if (prevCull == cullRect) {
+ // Skipped culls are tracked on the stack, but they point to the previous offset.
+ fCullOffsetStack.push(fCullOffsetStack.top());
+ return;
+ }
+
+ SkASSERT(prevCull.contains(cullRect));
+ }
+
+ uint32_t size = kPushCullOpSize;
+ size_t initialOffset = this->addDraw(PUSH_CULL, &size);
+ // PUSH_CULL's size should stay constant (used to rewind).
+ SkASSERT(size == kPushCullOpSize);
+
+ this->addRect(cullRect);
+ fCullOffsetStack.push(fWriter.bytesWritten());
+ this->addInt(0);
+ this->validate(initialOffset, size);
+}
+
+void SkPictureRecord::onPopCull() {
+ SkASSERT(!fCullOffsetStack.isEmpty());
+
+ uint32_t cullSkipOffset = fCullOffsetStack.top();
+ fCullOffsetStack.pop();
+
+ // Skipped push, do the same for pop.
+ if (!fCullOffsetStack.isEmpty() && cullSkipOffset == fCullOffsetStack.top()) {
+ return;
+ }
+
+ // Collapse empty push/pop pairs.
+ if ((size_t)(cullSkipOffset + kUInt32Size) == fWriter.bytesWritten()) {
+ SkASSERT(fWriter.bytesWritten() >= kPushCullOpSize);
+ SkASSERT(PUSH_CULL == peek_op(&fWriter, fWriter.bytesWritten() - kPushCullOpSize));
+ fWriter.rewindToOffset(fWriter.bytesWritten() - kPushCullOpSize);
+ return;
+ }
+
+ // op only
+ uint32_t size = kUInt32Size;
+ size_t initialOffset = this->addDraw(POP_CULL, &size);
+
+ // update the cull skip offset to point past this op.
+ fWriter.overwriteTAt<uint32_t>(cullSkipOffset, fWriter.bytesWritten());
+
+ this->validate(initialOffset, size);
+}
+
///////////////////////////////////////////////////////////////////////////////
SkSurface* SkPictureRecord::onNewSurface(const SkImageInfo& info) {