| /* |
| * Copyright 2019 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "gm/gm.h" |
| #include "include/core/SkCanvas.h" |
| #include "include/core/SkColor.h" |
| #include "include/core/SkImageFilter.h" |
| #include "include/core/SkPaint.h" |
| #include "include/core/SkPictureRecorder.h" |
| #include "include/core/SkRect.h" |
| #include "include/core/SkRefCnt.h" |
| #include "include/core/SkScalar.h" |
| #include "include/core/SkShader.h" |
| #include "include/core/SkTypes.h" |
| #include "include/effects/SkGradientShader.h" |
| #include "include/effects/SkImageFilters.h" |
| #include "src/core/SkCanvasPriv.h" |
| |
| #include <initializer_list> |
| |
| // Make a noisy (with hard-edges) background, so we can see the effect of the blur |
| // |
| static sk_sp<SkShader> make_shader(SkScalar cx, SkScalar cy, SkScalar rad) { |
| const SkColor colors[] = { |
| SK_ColorRED, SK_ColorRED, SK_ColorBLUE, SK_ColorBLUE, SK_ColorGREEN, SK_ColorGREEN, |
| SK_ColorRED, SK_ColorRED, SK_ColorBLUE, SK_ColorBLUE, SK_ColorGREEN, SK_ColorGREEN, |
| }; |
| constexpr int count = std::size(colors); |
| SkScalar pos[count] = { 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6 }; |
| for (int i = 0; i < count; ++i) { |
| pos[i] *= 1.0f/6; |
| } |
| return SkGradientShader::MakeSweep(cx, cy, colors, pos, count); |
| } |
| |
| static void do_draw(SkCanvas* canvas, bool useClip, bool useHintRect, SkScalar scaleFactor) { |
| SkAutoCanvasRestore acr(canvas, true); |
| canvas->clipRect({0, 0, 256, 256}); |
| |
| const SkScalar cx = 128, cy = 128, rad = 100; |
| SkPaint p; |
| p.setShader(make_shader(cx, cy, rad)); |
| p.setAntiAlias(true); |
| canvas->drawCircle(cx, cy, rad, p); |
| |
| // now setup a saveLayer that will pull in the backdrop and blur it |
| // |
| const SkRect r = {cx-50, cy-50, cx+50, cy+50}; |
| const SkRect* drawrptr = useHintRect ? &r : nullptr; |
| const SkScalar sigma = 10; |
| if (useClip) { |
| canvas->clipRect(r); |
| } |
| // Using kClamp because kDecal, the default, produces transparency near the edge of the canvas's |
| // device. |
| auto blur = SkImageFilters::Blur(sigma, sigma, SkTileMode::kClamp, nullptr); |
| auto rec = SkCanvasPriv::ScaledBackdropLayer(drawrptr, nullptr, blur.get(), scaleFactor, 0); |
| canvas->saveLayer(rec); |
| // draw something inside, just to demonstrate that we don't blur the new contents, |
| // just the backdrop. |
| p.setColor(SK_ColorYELLOW); |
| p.setShader(nullptr); |
| canvas->drawCircle(cx, cy, 30, p); |
| canvas->restore(); |
| } |
| |
| /* |
| * Draws a 2x4 grid of sweep circles. |
| * - for a given row, each col should be identical (canvas, picture) |
| * - row:0 no-hint-rect no-clip-rect expect big blur (except inner circle) |
| * - row:1 no-hint-rect clip-rect expect small blur (except inner circle) |
| * - row:2 hint-rect no-clip-rect expect big blur (except inner circle) |
| * - row:3 hint-rect clip-rect expect small blur (except inner circle) |
| * |
| * The test is that backdrop effects should be independent of the hint-rect, but should |
| * respect the clip-rect. |
| */ |
| DEF_SIMPLE_GM(backdrop_hintrect_clipping, canvas, 512, 1024) { |
| for (bool useHintRect : {false, true}) { |
| for (bool useClip : {false, true}) { |
| canvas->save(); |
| do_draw(canvas, useClip, useHintRect, 1.0f); |
| |
| SkPictureRecorder rec; |
| do_draw(rec.beginRecording(256, 256), useClip, useHintRect, 1.0f); |
| canvas->translate(256, 0); |
| canvas->drawPicture(rec.finishRecordingAsPicture()); |
| canvas->restore(); |
| |
| canvas->translate(0, 256); |
| } |
| } |
| } |
| |
| /* |
| * Draws a 3x4 grid of sweep circles. |
| * - for a given row, each col should be identical except that the intermediate scale factor used |
| * to evaluate the backdrop follows (1.0, 0.25, 0.1). Rows follow same pattern as above. |
| * |
| * The test is that backdrop effects should be independent of the hint-rect, should respect the |
| * clip rect, and be logically consistent with the reduced intermediate scaling. |
| */ |
| DEF_SIMPLE_GM(backdrop_scalefactor, canvas, 768, 1024) { |
| for (bool useHintRect : {false, true}) { |
| for (bool useClip : {false, true}) { |
| canvas->save(); |
| do_draw(canvas, useClip, useHintRect, 1.0f); |
| canvas->translate(256, 0); |
| do_draw(canvas, useClip, useHintRect, 0.25f); |
| canvas->translate(256, 0); |
| do_draw(canvas, useClip, useHintRect, 0.1f); |
| canvas->restore(); |
| |
| canvas->translate(0, 256); |
| } |
| } |
| } |