try to make dashing faster, by allowing it to be expressed as an array of points

try to make dashing faster, by allowing it to be expressed as an array of points that we just draw as squares or circles. To trigger that, this CL introduces a virtual API on patheffect (where dashing happens) that allows the effect to return its "effect" as an array of points.

[reed1, 2012-09-04 15:43:03]

Proposed chanage to SkCanvas: static SkPoint* ptsAllocator(void* context, int numberOfPoints) { return (SkPoint*)sk_malloc_throw(numberOfPoints * sizeof(SkPoint*)); } void SkCanvas::drawPoints(PointMode mode, size_t count, const SkPoint pts[], const SkPaint& paint) { if ((long)count <= 0) { return; } SkASSERT(pts != NULL); if (paint.canComputeFastBounds()) { SkRect r; // special-case 2 points (common for drawing a single line) if (2 == count) { r.set(pts[0], pts[1]); } else { r.set(pts, count); } SkRect storage; if (this->quickReject(paint.computeFastStrokeBounds(r, &storage))) { return; } } /* * If the patheffect can be represented as an array of points, resolve that * here so the device doesn't need to. */ const SkPaint* paintPtr = &paint; SkPathEffect* pe = paint.getPathEffect(); SkLazyPaint lazyP; if (pe) { SkPathEffect::PointsRec src; SkPathEffect::PointsRec dst; src.fMode = mode; src.fCount = count; src.fPoints = pts; if (pe->filterPoints(src, paint, &dst, ptsAllocator, NULL)) { mode = dst.fMode; count = dst.fCount; pts = dst.fPoints; SkPaint* p = lazyP.set(*paint); p->setPathEffect(NULL); paintPtr = p; } } LOOPER_BEGIN(*paintPtr, SkDrawFilter::kPoint_Type) while (iter.next()) { iter.fDevice->drawPoints(iter, mode, count, pts, looper.paint()); } LOOPER_END }

[bsalomon, 2012-09-04 17:32:38]

On 2012/09/04 15:43:31, reed1 wrote: I might want to allocate differently depending on the mode so maybe: SkPoint* (*PointAllocator)(void* context, SkCanvas::PointMode mode, int numberOfPoints); or SkPoint* (*PointAllocator)(void* context, const PointsRec&);

[reed1, 2012-09-04 17:35:16]

... now with Mode parameter.

[bsalomon, 2012-09-04 18:36:41]

On 2012/09/04 17:35:16, reed1 wrote: > ... now with Mode parameter. LGTM

[reed1, 2012-09-04 20:36:39]

> rbench -repeat 30 -match dashline Before CL: running bench [640 480] dashline_2_circle 8888: cmsecs = 104.12 565: cmsecs = 104.31 GPU: cmsecs = 113.40 NULLGPU: cmsecs = 108.53 running bench [640 480] dashline_1_circle 8888: cmsecs = 15.02 565: cmsecs = 14.65 GPU: cmsecs = 104.14 NULLGPU: cmsecs = 99.89 running bench [640 480] dashline_0_circle 8888: cmsecs = 14.92 565: cmsecs = 14.54 GPU: cmsecs = 16.36 NULLGPU: cmsecs = 13.94 running bench [640 480] dashline_2_square 8888: cmsecs = 38.43 565: cmsecs = 38.42 GPU: cmsecs = 46.80 NULLGPU: cmsecs = 41.87 running bench [640 480] dashline_1_square 8888: cmsecs = 15.02 565: cmsecs = 14.52 GPU: cmsecs = 48.47 NULLGPU: cmsecs = 43.78 running bench [640 480] dashline_0_square 8888: cmsecs = 15.02 565: cmsecs = 14.61 GPU: cmsecs = 16.21 NULLGPU: cmsecs = 13.98 After CL: running bench [640 480] dashline_2_circle 8888: cmsecs = 106.42 565: cmsecs = 107.13 GPU: cmsecs = 116.68 NULLGPU: cmsecs = 111.69 running bench [640 480] dashline_1_circle 8888: cmsecs = 136.59 565: cmsecs = 132.32 GPU: cmsecs = 159.42 NULLGPU: cmsecs = 87.35 running bench [640 480] dashline_0_circle 8888: cmsecs = 15.69 565: cmsecs = 15.97 GPU: cmsecs = 16.84 NULLGPU: cmsecs = 14.23 running bench [640 480] dashline_2_square 8888: cmsecs = 40.22 565: cmsecs = 40.04 GPU: cmsecs = 48.62 NULLGPU: cmsecs = 43.52 running bench [640 480] dashline_1_square 8888: cmsecs = 5.70 565: cmsecs = 4.56 GPU: cmsecs = 140.12 NULLGPU: cmsecs = 66.46 running bench [640 480] dashline_0_square 8888: cmsecs = 15.76 565: cmsecs = 15.93 GPU: cmsecs = 16.64 NULLGPU: cmsecs = 13.88 Summary: 1. dash effect needs to fold width==0 and width==1 together (if it can see the matrix) 2. gpu (or its caller) needs to fold width==0 and width==1 together in drawPoints 3. gpu should probably never call back into SkDraw::drawPoints, for that is wicket slow (see dashline_1_square before and after) I want to address some of these before committing.