/* * Copyright 2014 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #include "gm.h" #include "SkCanvas.h" #include "SkTypeface.h" /* This test tries to define the effect of using hairline strokes on text. * Provides non-hairline images for reference and consistency checks. * glyph_pos_(h/n)_(s/f/b) * -> test hairline/non-hairline stroke/fill/stroke+fill. */ static const SkScalar kTextHeight = 14.0f; static const char kText[] = "Proportional Hamburgefons #% fi"; namespace skiagm { class GlyphPosGM : public GM { public: GlyphPosGM(SkScalar strokeWidth, SkPaint::Style strokeStyle) : fStrokeWidth(strokeWidth) , fStrokeStyle(strokeStyle) { } protected: SkString onShortName() override { SkString str("glyph_pos"); if (fStrokeWidth == 0.0f) { str.append("_h"); // h == Hairline. } else { str.append("_n"); // n == Normal. } if (fStrokeStyle == SkPaint::kStroke_Style) { str.append("_s"); } else if (fStrokeStyle == SkPaint::kFill_Style) { str.append("_f"); } else { str.append("_b"); // b == Both. } return str; } SkISize onISize() override { return SkISize::Make(800, 600); } void onDraw(SkCanvas* canvas) override { // There's a black pixel at 40, 40 for reference. canvas->drawPoint(40.0f, 40.0f, SK_ColorBLACK); // Two reference images. canvas->translate(50.0f, 50.0f); drawTestCase(canvas, 1.0f); canvas->translate(0.0f, 50.0f); drawTestCase(canvas, 3.0f); // Uniform scaling test. canvas->translate(0.0f, 100.0f); canvas->save(); canvas->scale(3.0f, 3.0f); drawTestCase(canvas, 1.0f); canvas->restore(); // Non-uniform scaling test. canvas->translate(0.0f, 100.0f); canvas->save(); canvas->scale(3.0f, 6.0f); drawTestCase(canvas, 1.0f); canvas->restore(); // Skew test. canvas->translate(0.0f, 80.0f); canvas->save(); canvas->scale(3.0f, 3.0f); SkMatrix skew; skew.setIdentity(); skew.setSkewX(8.0f / 25.0f); skew.setSkewY(2.0f / 25.0f); canvas->concat(skew); drawTestCase(canvas, 1.0f); canvas->restore(); // Perspective test. canvas->translate(0.0f, 80.0f); canvas->save(); SkMatrix perspective; perspective.setIdentity(); perspective.setPerspX(-SkScalarInvert(340)); perspective.setSkewX(8.0f / 25.0f); perspective.setSkewY(2.0f / 25.0f); canvas->concat(perspective); drawTestCase(canvas, 1.0f); canvas->restore(); } void drawTestCase(SkCanvas* canvas, SkScalar textScale) { SkPaint paint; paint.setColor(SK_ColorBLACK); paint.setAntiAlias(true); paint.setTextSize(kTextHeight * textScale); sk_tool_utils::set_portable_typeface(&paint); paint.setStrokeWidth(fStrokeWidth); paint.setStyle(fStrokeStyle); // This demonstrates that we can not measure the text if there's a device transform. The // canvas total matrix will end up being a device transform. bool drawRef = !(canvas->getTotalMatrix().getType() & ~(SkMatrix::kIdentity_Mask | SkMatrix::kTranslate_Mask)); SkRect bounds; if (drawRef) { SkScalar advance = paint.measureText(kText, sizeof(kText) - 1, &bounds); paint.setStrokeWidth(0.0f); paint.setStyle(SkPaint::kStroke_Style); // Green box is the measured text bounds. paint.setColor(SK_ColorGREEN); canvas->drawRect(bounds, paint); // Red line is the measured advance from the 0,0 of the text position. paint.setColor(SK_ColorRED); canvas->drawLine(0.0f, 0.0f, advance, 0.0f, paint); } // Black text is the testcase, eg. the text. paint.setColor(SK_ColorBLACK); paint.setStrokeWidth(fStrokeWidth); paint.setStyle(fStrokeStyle); canvas->drawText(kText, sizeof(kText) - 1, 0.0f, 0.0f, paint); if (drawRef) { SkScalar widths[sizeof(kText) - 1]; paint.getTextWidths(kText, sizeof(kText) - 1, widths, NULL); paint.setStrokeWidth(0.0f); paint.setStyle(SkPaint::kStroke_Style); // Magenta lines are the positions for the characters. paint.setColor(SK_ColorMAGENTA); SkScalar w = bounds.x(); for (size_t i = 0; i < sizeof(kText) - 1; ++i) { canvas->drawLine(w, 0.0f, w, 5.0f, paint); w += widths[i]; } } } private: SkScalar fStrokeWidth; SkPaint::Style fStrokeStyle; typedef GM INHERITED; }; ////////////////////////////////////////////////////////////////////////////// static GM* GlyphPosHairlineStrokeAndFillFactory(void*) { return new GlyphPosGM(0.0f, SkPaint::kStrokeAndFill_Style); } static GM* GlyphPosStrokeAndFillFactory(void*) { return new GlyphPosGM(1.2f, SkPaint::kStrokeAndFill_Style); } static GM* GlyphPosHairlineStrokeFactory(void*) { return new GlyphPosGM(0.0f, SkPaint::kStroke_Style); } static GM* GlyphPosStrokeFactory(void*) { return new GlyphPosGM(1.2f, SkPaint::kStroke_Style); } static GM* GlyphPosHairlineFillFactory(void*) { return new GlyphPosGM(0.0f, SkPaint::kFill_Style); } static GM* GlyphPosFillFactory(void*) { return new GlyphPosGM(1.2f, SkPaint::kFill_Style); } static GMRegistry reg1(GlyphPosHairlineStrokeAndFillFactory); static GMRegistry reg2(GlyphPosStrokeAndFillFactory); static GMRegistry reg3(GlyphPosHairlineStrokeFactory); static GMRegistry reg4(GlyphPosStrokeFactory); static GMRegistry reg5(GlyphPosHairlineFillFactory); static GMRegistry reg6(GlyphPosFillFactory); }