(pixels, offsetIn = 0, count = pixels.byteLength - offsetIn)
| 58 | this.scratch = new Uint8Array(this.pixelsToBytes(width) + width); |
| 59 | } |
| 60 | send(pixels, offsetIn = 0, count = pixels.byteLength - offsetIn) { |
| 61 | let width = this.windowWidth; |
| 62 | let mask = new Uint8Array(this.pixelsToBytes(width)) |
| 63 | pixels = (16 === this.depth) ? new Uint16Array(pixels) : new Uint8Array(pixels);; |
| 64 | let lines = Math.floor(count / width); |
| 65 | let bytes = this.scratch; |
| 66 | let key = this.key; |
| 67 | if (undefined === key) |
| 68 | mask.fill(1); |
| 69 | for (let line = 0, offset = offsetIn; line < lines; line++, offset += width) { |
| 70 | if (undefined !== key) { |
| 71 | // build mask |
| 72 | for (let x = 0; x < width; x++) { |
| 73 | let pixel = pixels[offset + x]; |
| 74 | mask[x] = (key != pixel); |
| 75 | } |
| 76 | } |
| 77 | |
| 78 | let position = 0; |
| 79 | for (let x = 0; x < width; ) { |
| 80 | let maskRunLength; |
| 81 | |
| 82 | if (undefined !== key) { |
| 83 | maskRunLength = 1; |
| 84 | while ((maskRunLength < 64) && ((x + maskRunLength) < width) && (mask[x] == mask[x + maskRunLength])) //@@ 64 is conservative... depends on run type |
| 85 | maskRunLength += 1; |
| 86 | } |
| 87 | else |
| 88 | maskRunLength = width; |
| 89 | |
| 90 | if (mask[x]) { |
| 91 | // visible pixels |
| 92 | while (maskRunLength) { |
| 93 | // is the start of this run a repeat? |
| 94 | if (maskRunLength >= 3) { |
| 95 | let repeatLength; |
| 96 | for (repeatLength = 0; repeatLength < maskRunLength; repeatLength++) { |
| 97 | if (pixels[offset + x] != pixels[offset + x + repeatLength]) |
| 98 | break; |
| 99 | } |
| 100 | if (repeatLength >= 3) { |
| 101 | if (repeatLength > 64) |
| 102 | repeatLength = 64; // maximum repeat length |
| 103 | bytes[position++] = 0x80 | (repeatLength - 1); // repeat op-code |
| 104 | bytes[position++] = pixels[offset + x] & 0xff; // repeat value |
| 105 | if (16 == this.depth) |
| 106 | bytes[position++] = pixels[offset + x] >> 8; // repeat value |
| 107 | maskRunLength -= repeatLength; |
| 108 | x += repeatLength; |
| 109 | continue; |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | // literal. find next repeat, if any, to see for how long the literal lasts. |
| 114 | let repeatStart = maskRunLength; |
| 115 | for (let j = 0; j < maskRunLength - 2; j++) { |
| 116 | if ((pixels[offset + x + j] != pixels[offset + x + j + 1]) || (pixels[offset + x + j] != pixels[offset + x + j + 2])) |
| 117 | continue; |
nothing calls this directly
no test coverage detected