skia2/gm/glyph_pos_align.cpp

67 lines
2.3 KiB
C++

/*
* 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 "SkGradientShader.h"
/**
* This test exercises drawPosTextH and drawPosText with every text align.
*/
static const int kWidth = 480;
static const int kHeight = 600;
static const SkScalar kTextHeight = 64.0f;
static const int kMaxStringLength = 12;
static void drawTestCase(SkCanvas*, const char*, SkScalar, const SkPaint&);
DEF_SIMPLE_GM_BG(glyph_pos_align, canvas, kWidth, kHeight, SK_ColorBLACK) {
SkPaint paint;
paint.setTextSize(kTextHeight);
paint.setFakeBoldText(true);
const SkColor colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE };
const SkPoint pts[] = {{0, 0}, {kWidth, kHeight}};
paint.setShader(SkGradientShader::MakeLinear(pts, colors, nullptr, SK_ARRAY_COUNT(colors),
SkShader::kMirror_TileMode));
paint.setTextAlign(SkPaint::kRight_Align);
drawTestCase(canvas, "Right Align", kTextHeight, paint);
paint.setTextAlign(SkPaint::kCenter_Align);
drawTestCase(canvas, "Center Align", 4 * kTextHeight, paint);
paint.setTextAlign(SkPaint::kLeft_Align);
drawTestCase(canvas, "Left Align", 7 * kTextHeight, paint);
}
void drawTestCase(SkCanvas* canvas, const char* text, SkScalar y, const SkPaint& paint) {
SkScalar widths[kMaxStringLength];
SkScalar posX[kMaxStringLength];
SkPoint pos[kMaxStringLength];
int length = SkToInt(strlen(text));
SkASSERT(length <= kMaxStringLength);
paint.getTextWidths(text, length, widths);
float originX;
switch (paint.getTextAlign()) {
case SkPaint::kRight_Align: originX = 1; break;
case SkPaint::kCenter_Align: originX = 0.5f; break;
case SkPaint::kLeft_Align: originX = 0; break;
default: SkFAIL("Invalid paint origin"); return;
}
float x = kTextHeight;
for (int i = 0; i < length; ++i) {
posX[i] = x + originX * widths[i];
pos[i].set(posX[i], i ? pos[i - 1].y() + 3 : y + kTextHeight);
x += widths[i];
}
canvas->drawPosTextH(text, length, posX, y, paint);
canvas->drawPosText(text, length, pos, paint);
}