1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
/*
* Copyright 2015 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 "SkShader.h"
// This class of GMs test how edges/verts snap near rounding boundaries in device space without
// anti-aliaing.
class PixelSnapGM : public skiagm::GM {
public:
PixelSnapGM() {}
protected:
// kTrans should be even or checkboards wont agree in different test cases.
static const int kTrans = 14;
static const int kLabelPad = 4;
// The inverse of this value should be a perfect SkScalar.
static const int kSubPixelSteps = 8;
static const int kLabelTextSize = 9;
SkISize onISize() override {
SkPaint labelPaint;
labelPaint.setAntiAlias(true);
labelPaint.setColor(SK_ColorWHITE);
labelPaint.setTextSize(SkIntToScalar(kLabelTextSize));
// Assert that we only render double digit labels
SkASSERT(kSubPixelSteps < 99);
// Pick 88 as widest possible label rendered (?)
int xoffset = SkScalarCeilToInt(labelPaint.measureText("88", 2));
int yoffset = SkScalarCeilToInt(labelPaint.getTextSize());
return SkISize::Make(kLabelPad + (kSubPixelSteps + 1) * kTrans + xoffset,
kLabelPad + (kSubPixelSteps + 1) * kTrans + yoffset);
}
void onDraw(SkCanvas* canvas) override {
SkPaint bgPaint;
bgPaint.setShader(
sk_tool_utils::create_checkerboard_shader(0xFFAAAAAA, 0xFF777777, 1))->unref();
canvas->drawPaint(bgPaint);
SkString offset;
SkPaint labelPaint;
labelPaint.setAntiAlias(true);
labelPaint.setColor(SK_ColorWHITE);
labelPaint.setTextSize(SkIntToScalar(kLabelTextSize));
SkPaint linePaint;
linePaint.setColor(SK_ColorWHITE);
// Draw row labels
static const SkScalar labelOffsetY = labelPaint.getTextSize() + kLabelPad;
SkScalar labelOffsetX = 0;
canvas->save();
canvas->translate(0, labelOffsetY);
for (int i = 0; i <= kSubPixelSteps; ++i) {
offset.printf("%d", i);
canvas->drawText(offset.c_str(), offset.size(),
0, i * kTrans + labelPaint.getTextSize(),
labelPaint);
labelOffsetX = SkTMax(labelPaint.measureText(offset.c_str(), offset.size()),
labelOffsetX);
}
canvas->restore();
labelOffsetX += kLabelPad;
labelOffsetX = SkScalarCeilToScalar(labelOffsetX);
// Draw col labels
canvas->save();
canvas->translate(labelOffsetX, 0);
for (int i = 0; i <= kSubPixelSteps; ++i) {
offset.printf("%d", i);
canvas->drawText(offset.c_str(), offset.size(),
i * SkIntToScalar(kTrans), labelPaint.getTextSize(),
labelPaint);
}
canvas->restore();
canvas->translate(labelOffsetX, labelOffsetY);
SkASSERT((SkScalar)(int)labelOffsetX == labelOffsetX);
SkASSERT((SkScalar)(int)labelOffsetY == labelOffsetY);
// Draw test case grid lines (Draw them all at pixel centers to hopefully avoid any
// snapping issues).
for (int i = 0; i <= kSubPixelSteps + 1; ++i) {
canvas->drawLine(0.5f,
i * SkIntToScalar(kTrans) + 0.5f,
SkIntToScalar(kTrans) * (kSubPixelSteps + 1) + 0.5f,
i * SkIntToScalar(kTrans) + 0.5f,
linePaint);
canvas->drawLine(i * SkIntToScalar(kTrans) + 0.5f,
0.5f,
i * SkIntToScalar(kTrans) + 0.5f,
SkIntToScalar(kTrans) * (kSubPixelSteps + 1) + 0.5f,
linePaint);
}
for (int i = 0; i <= kSubPixelSteps; ++i) {
for (int j = 0; j <= kSubPixelSteps; ++j) {
canvas->save();
// +1's account for the grid lines around each test case.
canvas->translate(j * (kTrans + 1.f/kSubPixelSteps) + 1,
i * (kTrans + 1.f/kSubPixelSteps) + 1);
this->drawElement(canvas);
canvas->restore();
}
}
}
virtual void drawElement(SkCanvas*) = 0;
private:
typedef skiagm::GM INHERITED;
};
class PointSnapGM : public PixelSnapGM {
protected:
SkString onShortName() override { return SkString("pixel_snap_point"); }
void drawElement(SkCanvas* canvas) override { canvas->drawPoint(1, 1, SK_ColorBLUE); }
private:
typedef PixelSnapGM INHERITED;
};
class LineSnapGM : public PixelSnapGM {
protected:
SkString onShortName() override { return SkString("pixel_snap_line"); }
void drawElement(SkCanvas* canvas) override {
SkPaint paint;
paint.setColor(SK_ColorGREEN);
// Draw a horizontal and vertical line, each length 3.
canvas->drawLine(1, 1, 4, 1, paint);
canvas->drawLine(6, 1, 6, 4, paint);
}
private:
typedef PixelSnapGM INHERITED;
};
class RectSnapGM : public PixelSnapGM {
protected:
SkString onShortName() override { return SkString("pixel_snap_rect"); }
void drawElement(SkCanvas* canvas) override {
SkPaint paint;
paint.setColor(SK_ColorRED);
canvas->drawRect(SkRect::MakeXYWH(1, 1, 3, 3), paint);
}
private:
typedef PixelSnapGM INHERITED;
};
class ComboSnapGM : public PixelSnapGM {
protected:
SkString onShortName() override { return SkString("pixel_snap_combo"); }
void drawElement(SkCanvas* canvas) override {
SkPaint paint;
paint.setAntiAlias(false);
// A rectangle that exactly covers a pixel, a point at each corner, 8 horiz/vert lines
// at rect corners (two at each corner, extending away from rect). They are drawn in this
// order lines (green), points (blue), rect(red).
SkRect rect = SkRect::MakeXYWH(3, 3, 1, 1);
paint.setColor(SK_ColorGREEN);
canvas->drawLine(3, 3, 0, 3, paint);
canvas->drawLine(3, 3, 3, 0, paint);
canvas->drawLine(4, 3, 7, 3, paint);
canvas->drawLine(4, 3, 4, 0, paint);
canvas->drawLine(3, 4, 0, 4, paint);
canvas->drawLine(3, 4, 3, 7, paint);
canvas->drawLine(4, 4, 7, 4, paint);
canvas->drawLine(4, 4, 4, 7, paint);
canvas->drawPoint(4, 3, SK_ColorBLUE);
canvas->drawPoint(4, 4, SK_ColorBLUE);
canvas->drawPoint(3, 3, SK_ColorBLUE);
canvas->drawPoint(3, 4, SK_ColorBLUE);
paint.setColor(SK_ColorRED);
canvas->drawRect(rect, paint);
}
private:
typedef PixelSnapGM INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
DEF_GM( return SkNEW(PointSnapGM); )
DEF_GM( return SkNEW(LineSnapGM); )
DEF_GM( return SkNEW(RectSnapGM); )
DEF_GM( return SkNEW(ComboSnapGM); )
|
