| /* |
| * Copyright 2011 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "include/core/SkCanvas.h" |
| #include "include/core/SkPaint.h" |
| #include "include/core/SkPath.h" |
| #include "samplecode/Sample.h" |
| |
| // ensure that we don't accidentally screw up the bounds when the oval is |
| // fractional, and the impl computes the center and radii, and uses them to |
| // reconstruct the edges of the circle. |
| // see bug# 1504910 |
| static void test_circlebounds(SkCanvas*) { |
| SkRect r = { 1.39999998f, 1, 21.3999996f, 21 }; |
| SkPath p; |
| p.addOval(r); |
| SkASSERT(r == p.getBounds()); |
| } |
| |
| class CircleView : public Sample { |
| SkString name() override { return SkString("Circles"); } |
| |
| void circle(SkCanvas* canvas, int width, bool aa) { |
| SkPaint paint; |
| |
| paint.setAntiAlias(aa); |
| if (width < 0) { |
| paint.setStyle(SkPaint::kFill_Style); |
| } else { |
| paint.setStyle(SkPaint::kStroke_Style); |
| paint.setStrokeWidth(SkIntToScalar(width)); |
| } |
| canvas->drawCircle(0, 0, 9.0f, paint); |
| if ((false)) { // avoid bit rot, suppress warning |
| test_circlebounds(canvas); |
| } |
| } |
| |
| void drawSix(SkCanvas* canvas, SkScalar dx, SkScalar dy) { |
| for (int width = -1; width <= 1; width++) { |
| canvas->save(); |
| circle(canvas, width, false); |
| canvas->translate(0, dy); |
| circle(canvas, width, true); |
| canvas->restore(); |
| canvas->translate(dx, 0); |
| } |
| } |
| |
| static void make_poly(SkPath* path, int n) { |
| if (n <= 0) { |
| return; |
| } |
| path->incReserve(n + 1); |
| path->moveTo(SK_Scalar1, 0); |
| SkScalar step = SK_ScalarPI * 2 / n; |
| SkScalar angle = 0; |
| for (int i = 1; i < n; i++) { |
| angle += step; |
| path->lineTo(SkScalarCos(angle), SkScalarSin(angle)); |
| } |
| path->close(); |
| } |
| |
| void onDrawContent(SkCanvas* canvas) override { |
| SkPaint paint; |
| paint.setAntiAlias(true); |
| paint.setStyle(SkPaint::kStroke_Style); |
| SkMatrix matrix; |
| matrix.setScale(SkIntToScalar(100), SkIntToScalar(100)); |
| matrix.postTranslate(SkIntToScalar(200), SkIntToScalar(200)); |
| canvas->concat(matrix); |
| for (int n = 3; n < 20; n++) { |
| SkPath path; |
| make_poly(&path, n); |
| SkAutoCanvasRestore acr(canvas, true); |
| canvas->rotate(SkIntToScalar(10) * (n - 3)); |
| canvas->translate(-SK_Scalar1, 0); |
| canvas->drawPath(path, paint); |
| } |
| } |
| }; |
| |
| DEF_SAMPLE( return new CircleView(); ) |