1 /*
2 * Copyright 2018 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 // This benchmark attempts to measure the time to do a fullscreen clear, an axis-aligned partial
9 // clear, and a clear restricted to an axis-aligned rounded rect. The fullscreen and axis-aligned
10 // partial clears on the GPU should follow a fast path that maps to backend-specialized clear
11 // operations, whereas the rounded-rect clear cannot be.
12
13 #include "Benchmark.h"
14
15 #include "SkCanvas.h"
16 #include "SkGradientShader.h"
17 #include "SkPaint.h"
18 #include "SkRect.h"
19 #include "SkRRect.h"
20
21 #include "GrRenderTargetContext.h"
22
make_shader()23 static sk_sp<SkShader> make_shader() {
24 static const SkPoint kPts[] = {{0, 0}, {10, 10}};
25 static const SkColor kColors[] = {SK_ColorBLUE, SK_ColorWHITE};
26 return SkGradientShader::MakeLinear(kPts, kColors, nullptr, 2, SkShader::kClamp_TileMode);
27 }
28
29 class ClearBench : public Benchmark {
30 public:
31 enum ClearType {
32 kFull_ClearType,
33 kPartial_ClearType,
34 kComplex_ClearType
35 };
36
ClearBench(ClearType type)37 ClearBench(ClearType type) : fType(type) {}
38
39 protected:
onGetName()40 const char* onGetName() override {
41 switch(fType) {
42 case kFull_ClearType:
43 return "Clear-Full";
44 case kPartial_ClearType:
45 return "Clear-Partial";
46 case kComplex_ClearType:
47 return "Clear-Complex";
48 }
49 SkASSERT(false);
50 return "Unreachable";
51 }
52
onDraw(int loops,SkCanvas * canvas)53 void onDraw(int loops, SkCanvas* canvas) override {
54 static const SkRect kPartialClip = SkRect::MakeLTRB(50, 50, 400, 400);
55 static const SkRRect kComplexClip = SkRRect::MakeRectXY(kPartialClip, 15, 15);
56 // Small to limit fill cost, but intersects the clips to confound batching
57 static const SkRect kInterruptRect = SkRect::MakeXYWH(200, 200, 3, 3);
58
59 // For the draw that sits between consecutive clears, use a shader that is simple but
60 // requires local coordinates so that Ganesh does not convert it into a solid color rect,
61 // which could then turn into a scissored-clear behind the scenes.
62 SkPaint interruptPaint;
63 interruptPaint.setShader(make_shader());
64
65 GrRenderTargetContext* rtc = canvas->internal_private_accessTopLayerRenderTargetContext();
66 if (rtc) {
67 // Tricks the GrRenderTargetOpList into thinking it cannot reset its draw op list on
68 // a fullscreen clear. If we don't do this, fullscreen clear ops would be created and
69 // constantly discard the previous iteration's op so execution would only invoke one
70 // actual clear on the GPU (not what we want to measure).
71 rtc->setNeedsStencil();
72 }
73
74 for (int i = 0; i < loops; i++) {
75 canvas->save();
76 switch(fType) {
77 case kPartial_ClearType:
78 canvas->clipRect(kPartialClip);
79 break;
80 case kComplex_ClearType:
81 canvas->clipRRect(kComplexClip);
82 break;
83 case kFull_ClearType:
84 // Don't add any extra clipping, since it defaults to the entire "device"
85 break;
86 }
87
88 // The clear we care about measuring
89 canvas->clear(SK_ColorBLUE);
90 canvas->restore();
91
92 // Perform as minimal a draw as possible that intersects with the clear region in
93 // order to prevent the clear ops from being batched together.
94 canvas->drawRect(kInterruptRect, interruptPaint);
95 }
96 }
97
98 private:
99 ClearType fType;
100 };
101
102 DEF_BENCH( return new ClearBench(ClearBench::kFull_ClearType); )
103 DEF_BENCH( return new ClearBench(ClearBench::kPartial_ClearType); )
104 DEF_BENCH( return new ClearBench(ClearBench::kComplex_ClearType); )
105