1/*
2 * Copyright (C) 2016 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#pragma once
18
19namespace android {
20namespace NinePatchUtils {
21
22static inline void SetLatticeDivs(SkCanvas::Lattice* lattice, const Res_png_9patch& chunk,
23        int width, int height) {
24    lattice->fXCount = chunk.numXDivs;
25    lattice->fYCount = chunk.numYDivs;
26    lattice->fXDivs = chunk.getXDivs();
27    lattice->fYDivs = chunk.getYDivs();
28
29    // We'll often see ninepatches where the last div is equal to the width or height.
30    // This doesn't provide any additional information and is not supported by Skia.
31    if (lattice->fXCount > 0 && width == lattice->fXDivs[lattice->fXCount - 1]) {
32        lattice->fXCount--;
33    }
34    if (lattice->fYCount > 0 && height == lattice->fYDivs[lattice->fYCount - 1]) {
35        lattice->fYCount--;
36    }
37}
38
39static inline int NumDistinctRects(const SkCanvas::Lattice& lattice) {
40    int xRects;
41    if (lattice.fXCount > 0) {
42        xRects = (0 == lattice.fXDivs[0]) ? lattice.fXCount : lattice.fXCount + 1;
43    } else {
44        xRects = 1;
45    }
46
47    int yRects;
48    if (lattice.fYCount > 0) {
49        yRects = (0 == lattice.fYDivs[0]) ? lattice.fYCount : lattice.fYCount + 1;
50    } else {
51        yRects = 1;
52    }
53    return xRects * yRects;
54}
55
56static inline void SetLatticeFlags(SkCanvas::Lattice* lattice, SkCanvas::Lattice::Flags* flags,
57        int numFlags, const Res_png_9patch& chunk) {
58    lattice->fFlags = flags;
59    sk_bzero(flags, numFlags * sizeof(SkCanvas::Lattice::Flags));
60
61    bool needPadRow = lattice->fYCount > 0 && 0 == lattice->fYDivs[0];
62    bool needPadCol = lattice->fXCount > 0 && 0 == lattice->fXDivs[0];
63
64    int yCount = lattice->fYCount;
65    if (needPadRow) {
66        // Skip flags for the degenerate first row of rects.
67        flags += lattice->fXCount + 1;
68        yCount--;
69    }
70
71    int i = 0;
72    bool setFlags = false;
73    for (int y = 0; y < yCount + 1; y++) {
74        for (int x = 0; x < lattice->fXCount + 1; x++) {
75            if (0 == x && needPadCol) {
76                // First rect of each column is degenerate, skip the flag.
77                flags++;
78                continue;
79            }
80
81            if (0 == chunk.getColors()[i++]) {
82                *flags = SkCanvas::Lattice::kTransparent_Flags;
83                setFlags = true;
84            }
85
86            flags++;
87        }
88    }
89
90    if (!setFlags) {
91        lattice->fFlags = nullptr;
92    }
93}
94
95}; // namespace NinePatchUtils
96}; // namespace android
97