| /* |
| * Copyright 2016 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include <functional> |
| #include "SkCanvas.h" |
| #include "gm.h" |
| |
| static constexpr SkScalar kStarts[] = {0.f, 10.f, 30.f, 45.f, 90.f, 165.f, 180.f, 270.f}; |
| static constexpr SkScalar kSweeps[] = {1.f, 45.f, 90.f, 130.f, 180.f, 184.f, 300.f, 355.f}; |
| static constexpr SkScalar kDiameter = 40.f; |
| static constexpr SkRect kRect = {0.f, 0.f, kDiameter, kDiameter}; |
| static constexpr int kW = 1000; |
| static constexpr int kH = 1000; |
| static constexpr SkScalar kPad = 20.f; |
| |
| void draw_arcs(SkCanvas* canvas, std::function<void(SkPaint*)> configureStyle) { |
| // Draws grid of arcs with different start/sweep angles in red and their complement arcs in |
| // blue. |
| auto drawGrid = [canvas, &configureStyle] (SkScalar x, SkScalar y, bool useCenter, bool aa) { |
| SkPaint p0; |
| p0.setColor(SK_ColorRED); |
| p0.setAntiAlias(aa); |
| // Set a reasonable stroke width that configureStyle can override. |
| p0.setStrokeWidth(15.f); |
| SkPaint p1 = p0; |
| p1.setColor(SK_ColorBLUE); |
| // Use alpha so we see magenta on overlap between arc and its complement. |
| p0.setAlpha(100); |
| p1.setAlpha(100); |
| configureStyle(&p0); |
| configureStyle(&p1); |
| |
| canvas->save(); |
| canvas->translate(kPad + x, kPad + y); |
| for (auto start : kStarts) { |
| canvas->save(); |
| for (auto sweep : kSweeps) { |
| canvas->drawArc(kRect, start, sweep, useCenter, p0); |
| canvas->drawArc(kRect, start, -(360.f - sweep), useCenter, p1); |
| canvas->translate(kRect.width() + kPad, 0.f); |
| } |
| canvas->restore(); |
| canvas->translate(0, kRect.height() + kPad); |
| } |
| canvas->restore(); |
| }; |
| // Draw a grids for combo of enabling/disabling aa and using center. |
| static constexpr SkScalar kGridW = kW / 2.f; |
| static constexpr SkScalar kGridH = kH / 2.f; |
| drawGrid(0.f , 0.f , false, false); |
| drawGrid(kGridW, 0.f , true , false); |
| drawGrid(0.f , kGridH, false, true ); |
| drawGrid(kGridW, kGridH, true , true ); |
| // Draw separators between the grids. |
| SkPaint linePaint; |
| linePaint.setAntiAlias(true); |
| linePaint.setColor(SK_ColorBLACK); |
| canvas->drawLine(kGridW, 0.f , kGridW, SkIntToScalar(kH), linePaint); |
| canvas->drawLine(0.f , kGridH, SkIntToScalar(kW), kGridH, linePaint); |
| } |
| |
| #define DEF_ARC_GM(name) DEF_SIMPLE_GM(circular_arcs_##name, canvas, kW, kH) |
| |
| DEF_ARC_GM(fill) { |
| auto setFill = [] (SkPaint*p) { p->setStyle(SkPaint::kFill_Style); }; |
| draw_arcs(canvas, setFill); |
| } |
| |
| DEF_ARC_GM(hairline) { |
| auto setHairline = [] (SkPaint* p) { |
| p->setStyle(SkPaint::kStroke_Style); |
| p->setStrokeWidth(0.f); |
| }; |
| draw_arcs(canvas, setHairline); |
| } |
| |
| DEF_ARC_GM(stroke_butt) { |
| auto setStroke = [](SkPaint* p) { |
| p->setStyle(SkPaint::kStroke_Style); |
| p->setStrokeCap(SkPaint::kButt_Cap); |
| }; |
| draw_arcs(canvas, setStroke); |
| } |
| |
| DEF_ARC_GM(stroke_square) { |
| auto setStroke = [] (SkPaint* p) { |
| p->setStyle(SkPaint::kStroke_Style); |
| p->setStrokeCap(SkPaint::kSquare_Cap); |
| }; |
| draw_arcs(canvas, setStroke); |
| } |
| |
| DEF_ARC_GM(stroke_round) { |
| auto setStroke = [] (SkPaint* p) { |
| p->setStyle(SkPaint::kStroke_Style); |
| p->setStrokeCap(SkPaint::kRound_Cap); |
| }; |
| draw_arcs(canvas, setStroke); |
| } |
| |
| DEF_ARC_GM(stroke_and_fill_butt) { |
| auto setStroke = [] (SkPaint* p) { |
| p->setStyle(SkPaint::kStrokeAndFill_Style); |
| p->setStrokeCap(SkPaint::kButt_Cap); |
| }; |
| draw_arcs(canvas, setStroke); |
| } |
| |
| DEF_ARC_GM(stroke_and_fill_square) { |
| auto setStroke = [] (SkPaint* p) { |
| p->setStyle(SkPaint::kStrokeAndFill_Style); |
| p->setStrokeCap(SkPaint::kSquare_Cap); |
| }; |
| draw_arcs(canvas, setStroke); |
| } |
| |
| DEF_ARC_GM(stroke_and_fill_round) { |
| auto setStroke = [] (SkPaint* p) { |
| p->setStyle(SkPaint::kStrokeAndFill_Style); |
| p->setStrokeCap(SkPaint::kRound_Cap); |
| }; |
| draw_arcs(canvas, setStroke); |
| } |