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>

1 files changed, 7 insertions, 37 deletions

diff --git a/src/gpu/GrSWMaskHelper.cpp b/src/gpu/GrSWMaskHelper.cpp
index eb3986525e..af0d1bdc22 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(
@@ -105,39 +105,9 @@ 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);
-}