Add the machinery to GrDrawTarget to enable topological sorting

src/gpu/GrDrawTarget.cpp

 
 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrDrawTarget.h"
 
@@ skipping 20 matching lines @@
 #include "SkStrokeRec.h"
 
 ////////////////////////////////////////////////////////////////////////////////
 
 GrDrawTarget::GrDrawTarget(GrGpu* gpu, GrResourceProvider* resourceProvider)
     : fGpu(SkRef(gpu))
     , fResourceProvider(resourceProvider)
     , fFlushState(fGpu, fResourceProvider, 0)
     , fFlushing(false)
     , fFirstUnpreparedBatch(0)
-    , fClosed(false) {
+    , fFlags(0) {
     // TODO: Stop extracting the context (currently needed by GrClipMaskManager)
     fContext = fGpu->getContext();
     fClipMaskManager.reset(new GrClipMaskManager(this));
 }
 
 GrDrawTarget::~GrDrawTarget() {
     fGpu->unref();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
+// Add a GrDrawTarget-based dependency
+void GrDrawTarget::addDependency(GrDrawTarget* dependedOn) {
+    SkASSERT(!dependedOn->dependsOn(this));  // loops are bad
+
+    if (this->dependsOn(dependedOn)) {
+        return;  // don't add duplicate dependencies
+    }
+
+    *fDependencies.push() = dependedOn;
+}
+
+// Convert from a GrSurface-based dependency to a GrDrawTarget one
+void GrDrawTarget::addDependency(GrSurface* dependedOn) {
+    if (dependedOn->asRenderTarget() && dependedOn->asRenderTarget()->getLastDrawTarget()) {
+        // If it is still receiving dependencies, this DT shouldn't be closed
+        SkASSERT(!this->isClosed());
+
+        GrDrawTarget* dt = dependedOn->asRenderTarget()->getLastDrawTarget();
+        if (dt == this) {
+            // self-read - presumably for dst reads
+        } else {
+            this->addDependency(dt);
+
+            // Can't make it closed in the self-read case
+            dt->makeClosed();
+        }
+    }
+}
+
 bool GrDrawTarget::setupDstReadIfNecessary(const GrPipelineBuilder& pipelineBuilder,
                                            const GrProcOptInfo& colorPOI,
                                            const GrProcOptInfo& coveragePOI,
                                            GrXferProcessor::DstTexture* dstTexture,
                                            const SkRect& batchBounds) {
     SkRect bounds = batchBounds;
     bounds.outset(0.5f, 0.5f);
 
     if (!pipelineBuilder.willXPNeedDstTexture(*this->caps(), colorPOI, coveragePOI)) {
         return true;
@@ skipping 344 matching lines @@
 }
 
 template <class Left, class Right> static bool intersect(const Left& a, const Right& b) {
     SkASSERT(a.fLeft <= a.fRight && a.fTop <= a.fBottom &&
              b.fLeft <= b.fRight && b.fTop <= b.fBottom);
     return a.fLeft < b.fRight && b.fLeft < a.fRight && a.fTop < b.fBottom && b.fTop < a.fBottom;
 }
 
 void GrDrawTarget::recordBatch(GrBatch* batch) {
     // A closed drawTarget should never receive new/more batches
-    SkASSERT(!fClosed);
+    SkASSERT(!this->isClosed());
 
     // Check if there is a Batch Draw we can batch with by linearly searching back until we either
     // 1) check every draw
     // 2) intersect with something
     // 3) find a 'blocker'
     // Experimentally we have found that most batching occurs within the first 10 comparisons.
     static const int kMaxLookback = 10;
 
     GrBATCH_INFO("Re-Recording (%s, B%u)\n"
         "\tBounds LRTB (%f, %f, %f, %f)\n",
@@ skipping 63 matching lines @@
     }
 
     return true;
 }
 
 void GrDrawTarget::clearStencilClip(const SkIRect& rect, bool insideClip, GrRenderTarget* rt) {
     GrBatch* batch = new GrClearStencilClipBatch(rect, insideClip, rt);
     this->recordBatch(batch);
     batch->unref();
 }