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/*
* 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_always(&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);
}