TestUtils.cpp revision a1717271caac5e8ea3808c331d4141ac01a42134 
1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "TestUtils.h"
18
19namespace android {
20namespace uirenderer {
21
22SkColor TestUtils::interpolateColor(float fraction, SkColor start, SkColor end) {
23    int startA = (start >> 24) & 0xff;
24    int startR = (start >> 16) & 0xff;
25    int startG = (start >> 8) & 0xff;
26    int startB = start & 0xff;
27
28    int endA = (end >> 24) & 0xff;
29    int endR = (end >> 16) & 0xff;
30    int endG = (end >> 8) & 0xff;
31    int endB = end & 0xff;
32
33    return (int)((startA + (int)(fraction * (endA - startA))) << 24)
34            | (int)((startR + (int)(fraction * (endR - startR))) << 16)
35            | (int)((startG + (int)(fraction * (endG - startG))) << 8)
36            | (int)((startB + (int)(fraction * (endB - startB))));
37}
38
39void TestUtils::drawTextToCanvas(TestCanvas* canvas, const char* text,
40        const SkPaint& inPaint, float x, float y) {
41   // copy to force TextEncoding (which JNI layer would have done)
42   SkPaint paint(inPaint);
43   paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
44
45   SkMatrix identity;
46   identity.setIdentity();
47   SkSurfaceProps surfaceProps(0, kUnknown_SkPixelGeometry);
48   SkAutoGlyphCacheNoGamma autoCache(paint, &surfaceProps, &identity);
49
50   float totalAdvance = 0;
51   std::vector<glyph_t> glyphs;
52   std::vector<float> positions;
53   Rect bounds;
54   while (*text != '\0') {
55       SkUnichar unichar = SkUTF8_NextUnichar(&text);
56       glyph_t glyph = autoCache.getCache()->unicharToGlyph(unichar);
57       autoCache.getCache()->unicharToGlyph(unichar);
58
59       // push glyph and its relative position
60       glyphs.push_back(glyph);
61       positions.push_back(totalAdvance);
62       positions.push_back(0);
63
64       // compute bounds
65       SkGlyph skGlyph = autoCache.getCache()->getUnicharMetrics(unichar);
66       Rect glyphBounds(skGlyph.fWidth, skGlyph.fHeight);
67       glyphBounds.translate(totalAdvance + skGlyph.fLeft, skGlyph.fTop);
68       bounds.unionWith(glyphBounds);
69
70       // advance next character
71       SkScalar skWidth;
72       paint.getTextWidths(&glyph, sizeof(glyph), &skWidth, NULL);
73       totalAdvance += skWidth;
74   }
75   bounds.translate(x, y);
76   canvas->drawText(glyphs.data(), positions.data(), glyphs.size(), paint, x, y,
77           bounds.left, bounds.top, bounds.right, bounds.bottom, totalAdvance);
78}
79
80} /* namespace uirenderer */
81} /* namespace android */
82