Incrementally flush GrDrawTarget

src/gpu/GrDrawTarget.cpp

Index: src/gpu/GrDrawTarget.cpp
diff --git a/src/gpu/GrDrawTarget.cpp b/src/gpu/GrDrawTarget.cpp
index e7c1c8b5c14a93733bfca40cd8a7b99a82f7b4dd..bf2391666b1dc9ec78951c09712832cfe9962d71 100644
--- a/src/gpu/GrDrawTarget.cpp
+++ b/src/gpu/GrDrawTarget.cpp
@@ -36,7 +36,8 @@ GrDrawTarget::GrDrawTarget(GrGpu* gpu, GrResourceProvider* resourceProvider)
     : fGpu(SkRef(gpu))
     , fResourceProvider(resourceProvider)
     , fFlushing(false)
-    , fLastFlushToken(0) {
+    , fLastFlushToken(0)
+    , fLastFlushedBatch(0) {
     // TODO: Stop extracting the context (currently needed by GrClipMaskManager)
     fContext = fGpu->getContext();
     fClipMaskManager.reset(new GrClipMaskManager(this));
@@ -111,7 +112,8 @@ bool GrDrawTarget::setupDstReadIfNecessary(const GrPipelineBuilder& pipelineBuil
     return true;
 }
 
-void GrDrawTarget::flush() {
+void GrDrawTarget::flushN(int N) {
+    SkASSERT(fLastFlushedBatch + N <= fBatches.count());
     if (fFlushing) {
         return;
     }
@@ -119,8 +121,10 @@ void GrDrawTarget::flush() {
 
     GrBatchFlushState flushState(fGpu, fResourceProvider, fLastFlushToken);
 
+    int flushTo = fLastFlushedBatch + N;
+
     // Loop over all batches and generate geometry
-    for (int i = 0; i < fBatches.count(); ++i) {
+    for (int i = fLastFlushedBatch; i < flushTo; ++i) {
         fBatches[i]->prepare(&flushState);
     }
 
@@ -128,17 +132,22 @@ void GrDrawTarget::flush() {
     flushState.preIssueDraws();
 
     // Draw all the generated geometry.
-    for (int i = 0; i < fBatches.count(); ++i) {
+    for (int i = fLastFlushedBatch; i < flushTo; ++i) {
         fBatches[i]->draw(&flushState);
     }
 
     fLastFlushToken = flushState.lastFlushedToken();
 
     fFlushing = false;
+}
+
+void GrDrawTarget::flush() {
+    this->flushN(fBatches.count() - fLastFlushedBatch);
     this->reset();
 }
 
 void GrDrawTarget::reset() {
+    fLastFlushedBatch = 0;
     fBatches.reset();
 }
 
@@ -434,6 +443,10 @@ void GrDrawTarget::recordBatch(GrBatch* batch) {
         GrBATCH_INFO("\t\tFirstBatch\n");
     }
     fBatches.push_back().reset(SkRef(batch));
+    if (fBatches.count() > kMaxLookback) {
+        this->flushN(1);

[bsalomon, 2015/10/02 13:56:37]

Maybe assert that we're only 1 ahead? Otherwise, lgtm.

+        fLastFlushedBatch++;
+    }
 }
 
 ///////////////////////////////////////////////////////////////////////////////