| /* |
| * 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. |
| */ |
| constexpr SkScalar kTextHeight = 14.0f; |
| constexpr char kText[] = "Proportional Hamburgefons #% fi"; |
| |
| static void drawTestCase(SkCanvas* canvas, |
| SkScalar textScale, |
| SkScalar strokeWidth, |
| SkPaint::Style strokeStyle); |
| |
| static void draw_gm(SkCanvas* canvas, |
| SkScalar strokeWidth, |
| SkPaint::Style strokeStyle) { |
| // There's a black pixel at 40, 40 for reference. |
| canvas->drawPoint(40, 40, SkPaint()); |
| |
| // Two reference images. |
| canvas->translate(50.0f, 50.0f); |
| drawTestCase(canvas, 1.0f, strokeWidth, strokeStyle); |
| |
| canvas->translate(0.0f, 50.0f); |
| drawTestCase(canvas, 3.0f, strokeWidth, strokeStyle); |
| |
| // Uniform scaling test. |
| canvas->translate(0.0f, 100.0f); |
| canvas->save(); |
| canvas->scale(3.0f, 3.0f); |
| drawTestCase(canvas, 1.0f, strokeWidth, strokeStyle); |
| canvas->restore(); |
| |
| // Non-uniform scaling test. |
| canvas->translate(0.0f, 100.0f); |
| canvas->save(); |
| canvas->scale(3.0f, 6.0f); |
| drawTestCase(canvas, 1.0f, strokeWidth, strokeStyle); |
| 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, strokeWidth, strokeStyle); |
| 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, strokeWidth, strokeStyle); |
| canvas->restore(); |
| } |
| |
| static void drawTestCase(SkCanvas* canvas, |
| SkScalar textScale, |
| SkScalar strokeWidth, |
| SkPaint::Style strokeStyle) { |
| SkPaint paint; |
| paint.setColor(SK_ColorBLACK); |
| paint.setAntiAlias(true); |
| paint.setTextSize(kTextHeight * textScale); |
| sk_tool_utils::set_portable_typeface(&paint); |
| paint.setStrokeWidth(strokeWidth); |
| paint.setStyle(strokeStyle); |
| |
| // 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(strokeWidth); |
| paint.setStyle(strokeStyle); |
| 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, nullptr); |
| |
| 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]; |
| } |
| } |
| } |
| |
| DEF_SIMPLE_GM(glyph_pos_h_b, c, 800, 600) { |
| draw_gm(c, 0.0f, SkPaint::kStrokeAndFill_Style); |
| } |
| DEF_SIMPLE_GM(glyph_pos_n_b, c, 800, 600) { |
| draw_gm(c, 1.2f, SkPaint::kStrokeAndFill_Style); |
| } |
| DEF_SIMPLE_GM(glyph_pos_h_s, c, 800, 600) { |
| draw_gm(c, 0.0f, SkPaint::kStroke_Style); |
| } |
| DEF_SIMPLE_GM(glyph_pos_n_s, c, 800, 600) { |
| draw_gm(c, 1.2f, SkPaint::kStroke_Style); |
| } |
| DEF_SIMPLE_GM(glyph_pos_h_f, c, 800, 600) { |
| draw_gm(c, 0.0f, SkPaint::kFill_Style); |
| } |
| DEF_SIMPLE_GM(glyph_pos_n_f, c, 800, 600) { |
| draw_gm(c, 1.2f, SkPaint::kFill_Style); |
| } |