commit-bot@chromium.org | 064779a | 2013-07-01 17:50:29 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * CAUTION: EXPERIMENTAL CODE |
| 3 | * |
| 4 | * This code is not to be used and will not be supported |
| 5 | * if it fails on you. DO NOT USE! |
| 6 | * |
| 7 | */ |
| 8 | |
| 9 | #include "SkPathUtils.h" |
| 10 | |
| 11 | #include "SkPath.h" |
| 12 | #include "SkPathOps.h" // this can't be found, how do I link it? |
| 13 | #include "SkRegion.h" |
| 14 | |
| 15 | typedef void (*line2path)(SkPath*, const char*, int, int); |
| 16 | #define SQRT_2 1.41421356237f |
| 17 | #define ON 0xFF000000 // black pixel |
| 18 | #define OFF 0x00000000 // transparent pixel |
| 19 | |
| 20 | // assumes stride is in bytes |
| 21 | /* |
| 22 | static void FillRandomBits( int chars, char* bits ){ |
| 23 | SkTime time; |
| 24 | SkMWCRandom rand = SkMWCRandom( time.GetMSecs() ); |
| 25 | |
| 26 | for (int i = 0; i < chars; ++i){ |
| 27 | bits[i] = rand.nextU(); |
| 28 | } |
| 29 | }OA |
| 30 | */ |
| 31 | |
| 32 | static int GetBit( const char* buffer, int x ) { |
| 33 | int byte = x >> 3; |
| 34 | int bit = x & 7; |
| 35 | |
| 36 | return buffer[byte] & (128 >> bit); |
| 37 | } |
| 38 | |
| 39 | /* |
| 40 | static void Line2path_pixel(SkPath* path, const char* line, |
| 41 | int lineIdx, int width) { |
| 42 | for (int i = 0; i < width; ++i) { |
| 43 | // simply makes every ON pixel into a rect path |
| 44 | if (GetBit(line,i)) { |
| 45 | path->addRect(SkRect::MakeXYWH(i, lineIdx, 1, 1), |
| 46 | SkPath::kCW_Direction); |
| 47 | } |
| 48 | } |
| 49 | } |
| 50 | |
| 51 | static void Line2path_pixelCircle(SkPath* path, const char* line, |
| 52 | int lineIdx, int width) { |
| 53 | for (int i = 0; i < width; ++i) { |
| 54 | // simply makes every ON pixel into a circle path |
| 55 | if (GetBit(line,i)) { |
| 56 | path->addCircle(i + SK_ScalarHalf, |
| 57 | lineIdx + SK_ScalarHalf, |
| 58 | SkFloatToScalar(SQRT_2 / 2.0f)); |
| 59 | } |
| 60 | } |
| 61 | } |
| 62 | */ |
| 63 | |
| 64 | static void Line2path_span(SkPath* path, const char* line, |
| 65 | int lineIdx, int width) { |
| 66 | bool inRun = 0; |
| 67 | int start = 1; |
| 68 | |
| 69 | for (int i = 0; i < width; ++i) { |
| 70 | int curPixel = GetBit(line,i); |
| 71 | |
| 72 | if ( (curPixel!=0) != inRun ) { // if transition |
| 73 | if (curPixel) { // if transition on |
| 74 | inRun = 1; |
| 75 | start = i; // mark beginning of span |
| 76 | }else { // if transition off add the span as a path |
| 77 | inRun = 0; |
| 78 | path->addRect(SkRect::MakeXYWH(start, lineIdx, i-start, 1), |
| 79 | SkPath::kCW_Direction); |
| 80 | } |
| 81 | } |
| 82 | } |
| 83 | |
| 84 | if (inRun==1) { // close any open spans |
| 85 | int end = 0; |
| 86 | if ( GetBit(line,width-1) ) ++end; |
| 87 | path->addRect(SkRect::MakeXYWH(start, lineIdx, |
| 88 | width - 1 + end - start, 1), |
| 89 | SkPath::kCW_Direction); |
| 90 | } else if ( GetBit(line,width-1) ) { // if last pixel on add rect |
| 91 | path->addRect(SkRect::MakeXYWH(width-1, lineIdx, 1, 1), |
| 92 | SkPath::kCW_Direction); |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | void SkPathUtils::BitsToPath_Path(SkPath* path, |
| 97 | const char* bitmap, |
| 98 | int h, int w, int stride) { |
| 99 | // loop for every line in bitmap |
| 100 | for (int i = 0; i < h; ++i) { |
| 101 | // fn ptr handles each line separately |
| 102 | //l2p_fn(path, &bitmap[i*stride], i, w); |
| 103 | Line2path_span(path, &bitmap[i*stride], i, w); |
| 104 | } |
| 105 | Simplify(*path, path); // simplify resulting bitmap |
| 106 | } |
| 107 | |
| 108 | void SkPathUtils::BitsToPath_Region(SkPath* path, |
| 109 | const char* bitmap, |
| 110 | int h, int w, int stride) { |
| 111 | SkRegion region; |
| 112 | |
| 113 | // loop for each line |
| 114 | for (int y = 0; y < h; ++y){ |
| 115 | bool inRun = 0; |
| 116 | int start = 1; |
| 117 | const char* line = &bitmap[y * stride]; |
| 118 | |
| 119 | // loop for each pixel |
| 120 | for (int i = 0; i < w; ++i) { |
| 121 | int curPixel = GetBit(line,i); |
| 122 | |
| 123 | if ( (curPixel!=0) != inRun ) { // if transition |
| 124 | if (curPixel) { // if transition on |
| 125 | inRun = 1; |
| 126 | start = i; // mark beginning of span |
| 127 | }else { // if transition off add the span as a path |
| 128 | inRun = 0; |
| 129 | //add here |
| 130 | region.op(SkIRect::MakeXYWH(start, y, i-start, 1), |
| 131 | SkRegion::kUnion_Op ); |
| 132 | } |
| 133 | } |
| 134 | } |
| 135 | if (inRun==1) { // close any open spans |
| 136 | int end = 0; |
| 137 | if ( GetBit(line,w-1) ) ++end; |
| 138 | // add the thing here |
| 139 | region.op(SkIRect::MakeXYWH(start, y, w-1-start+end, 1), |
| 140 | SkRegion::kUnion_Op ); |
| 141 | |
| 142 | } else if ( GetBit(line,w-1) ) { // if last pixel on add rect |
| 143 | // add the thing here |
| 144 | region.op(SkIRect::MakeXYWH(w-1, y, 1, 1), |
| 145 | SkRegion::kUnion_Op ); |
| 146 | } |
| 147 | } |
| 148 | // convert region to path |
| 149 | region.getBoundaryPath(path); |
| 150 | } |