1/*
2 * Copyright 2014 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "gm.h"
9#include "SkCanvas.h"
10#include "SkGradientShader.h"
11
12/**
13 * This test exercises drawPosTextH and drawPosText with every text align.
14 */
15constexpr int kWidth = 480;
16constexpr int kHeight = 600;
17constexpr SkScalar kTextHeight = 64.0f;
18constexpr int kMaxStringLength = 12;
19
20static void drawTestCase(SkCanvas*, const char*, SkScalar, const SkPaint&);
21
22DEF_SIMPLE_GM_BG(glyph_pos_align, canvas, kWidth, kHeight, SK_ColorBLACK) {
23        SkPaint paint;
24        paint.setTextSize(kTextHeight);
25        paint.setFakeBoldText(true);
26        const SkColor colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE };
27        const SkPoint pts[] = {{0, 0}, {kWidth, kHeight}};
28        paint.setShader(SkGradientShader::MakeLinear(pts, colors, nullptr, SK_ARRAY_COUNT(colors),
29                                                     SkShader::kMirror_TileMode));
30        paint.setTextAlign(SkPaint::kRight_Align);
31        drawTestCase(canvas, "Right Align", kTextHeight, paint);
32
33        paint.setTextAlign(SkPaint::kCenter_Align);
34        drawTestCase(canvas, "Center Align", 4 * kTextHeight, paint);
35
36        paint.setTextAlign(SkPaint::kLeft_Align);
37        drawTestCase(canvas, "Left Align", 7 * kTextHeight, paint);
38}
39
40void drawTestCase(SkCanvas* canvas, const char* text, SkScalar y, const SkPaint& paint) {
41        SkScalar widths[kMaxStringLength];
42        SkScalar posX[kMaxStringLength];
43        SkPoint pos[kMaxStringLength];
44        int length = SkToInt(strlen(text));
45        SkASSERT(length <= kMaxStringLength);
46
47        paint.getTextWidths(text, length, widths);
48
49        float originX;
50        switch (paint.getTextAlign()) {
51            case SkPaint::kRight_Align: originX = 1; break;
52            case SkPaint::kCenter_Align: originX = 0.5f; break;
53            case SkPaint::kLeft_Align: originX = 0; break;
54            default: SK_ABORT("Invalid paint origin"); return;
55        }
56
57        float x = kTextHeight;
58        for (int i = 0; i < length; ++i) {
59            posX[i] = x + originX * widths[i];
60            pos[i].set(posX[i], i ? pos[i - 1].y() + 3 : y + kTextHeight);
61            x += widths[i];
62        }
63
64        canvas->drawPosTextH(text, length, posX, y, paint);
65        canvas->drawPosText(text, length, pos, paint);
66}
67