Revert "Threaded generation of software paths"

This reverts commit 76323bc0615044a5921afef0e19a350f3d04ffe0.

Reason for revert: Breaking NUC bots in threaded gm comparison:

https://chromium-swarm.appspot.com/task?id=382e589753187f10&refresh=10



Original change's description:
> Threaded generation of software paths
> 
> All information needed by the thread is captured by the prepare
> callback object, the lambda captures a pointer to that, and does the
> mask render. Once it's done, it signals the semaphore (also owned by the
> callback). The callback defers the semaphore wait even longer (into the
> ASAP upload), so the odds of waiting for the thread are REALLY low.
> 
> Also did a bunch of cleanup along the way, and put in some trace markers
> so we can monitor how well this is working.
> 
> Traces of a GM that includes GPU and SW path rendering (path-reverse):
> 
> Original:
>     https://screenshot.googleplex.com/f5BG3901tQg.png
> Threaded, with wait in the callback (notice pre flush callback blocking):
>     https://screenshot.googleplex.com/htOSZFE2s04.png
> Current version, with wait deferred to ASAP upload function:
>     https://screenshot.googleplex.com/GHjD0U3C34q.png
> 
> Bug: skia:
> Change-Id: I3d5a230bbd68eb35e1f0574b308485c691435790
> Reviewed-on: https://skia-review.googlesource.com/36560
> Commit-Queue: Brian Osman <brianosman@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>

TBR=egdaniel@google.com,mtklein@google.com,bsalomon@google.com,robertphillips@google.com,brianosman@google.com

Change-Id: Icac0918a3771859f671b69ae07ae0fedd3ebb3db
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/38560
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>

1 files changed, 37 insertions, 7 deletions

diff --git a/src/gpu/GrSWMaskHelper.cpp b/src/gpu/GrSWMaskHelper.cpp
index af0d1bdc22..eb3986525e 100644
--- a/src/gpu/GrSWMaskHelper.cpp
+++ b/src/gpu/GrSWMaskHelper.cpp
@@ -6,12 +6,12 @@
  */
 
 #include "GrSWMaskHelper.h"
-
 #include "GrContext.h"
 #include "GrContextPriv.h"
 #include "GrShape.h"
 #include "GrSurfaceContext.h"
 #include "GrTextureProxy.h"
+#include "SkDistanceFieldGen.h"
 
 /*
  * Convert a boolean operation into a transfer mode code
@@ -76,13 +76,13 @@ bool GrSWMaskHelper::init(const SkIRect& resultBounds, const SkMatrix* matrix) {
     SkIRect bounds = SkIRect::MakeWH(resultBounds.width(), resultBounds.height());
 
     const SkImageInfo bmImageInfo = SkImageInfo::MakeA8(bounds.width(), bounds.height());
-    if (!fPixels->tryAlloc(bmImageInfo)) {
+    if (!fPixels.tryAlloc(bmImageInfo)) {
         return false;
     }
-    fPixels->erase(0);
+    fPixels.erase(0);
 
     sk_bzero(&fDraw, sizeof(fDraw));
-    fDraw.fDst      = *fPixels;
+    fDraw.fDst      = fPixels;
     fRasterClip.setRect(bounds);
     fDraw.fRC       = &fRasterClip;
     fDraw.fMatrix   = &fMatrix;
@@ -92,8 +92,8 @@ bool GrSWMaskHelper::init(const SkIRect& resultBounds, const SkMatrix* matrix) {
 sk_sp<GrTextureProxy> GrSWMaskHelper::toTextureProxy(GrContext* context, SkBackingFit fit) {
     GrSurfaceDesc desc;
     desc.fOrigin = kTopLeft_GrSurfaceOrigin;
-    desc.fWidth = fPixels->width();
-    desc.fHeight = fPixels->height();
+    desc.fWidth = fPixels.width();
+    desc.fHeight = fPixels.height();
     desc.fConfig = kAlpha_8_GrPixelConfig;
 
     sk_sp<GrSurfaceContext> sContext = context->contextPriv().makeDeferredSurfaceContext(
@@ -105,9 +105,39 @@ sk_sp<GrTextureProxy> GrSWMaskHelper::toTextureProxy(GrContext* context, SkBacki
     }
 
     SkImageInfo ii = SkImageInfo::MakeA8(desc.fWidth, desc.fHeight);
-    if (!sContext->writePixels(ii, fPixels->addr(), fPixels->rowBytes(), 0, 0)) {
+    if (!sContext->writePixels(ii, fPixels.addr(), fPixels.rowBytes(), 0, 0)) {
         return nullptr;
     }
 
     return sContext->asTextureProxyRef();
 }
+
+/**
+ * Convert mask generation results to a signed distance field
+ */
+void GrSWMaskHelper::toSDF(unsigned char* sdf) {
+    SkGenerateDistanceFieldFromA8Image(sdf, (const unsigned char*)fPixels.addr(),
+                                       fPixels.width(), fPixels.height(), fPixels.rowBytes());
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/**
+ * Software rasterizes shape to A8 mask and uploads the result to a scratch texture. Returns the
+ * resulting texture on success; nullptr on failure.
+ */
+sk_sp<GrTextureProxy> GrSWMaskHelper::DrawShapeMaskToTexture(GrContext* context,
+                                                             const GrShape& shape,
+                                                             const SkIRect& resultBounds,
+                                                             GrAA aa,
+                                                             SkBackingFit fit,
+                                                             const SkMatrix* matrix) {
+    GrSWMaskHelper helper;
+
+    if (!helper.init(resultBounds, matrix)) {
+        return nullptr;
+    }
+
+    helper.drawShape(shape, SkRegion::kReplace_Op, aa, 0xFF);
+
+    return helper.toTextureProxy(context, fit);
+}