contexts = { const bufferU8 = new Uint8Array(256); const bufferU32 = new Uint32Array(bufferU8.buffer); for(let i = 0; i < bufferU8.length; i++){ bufferU8[i] = i; } // draw buffer values as 24x24 pixels const columns8 = (width-4)/24 | 0; const columns32 = ((width-4)/(24*4) | 0)*4; const rowsU8 = Math.ceil(bufferU8.length / columns8); const rowsU32 = Math.ceil(bufferU8.length / columns32); const cHeightU8 = rowsU8 * 26 + 2; const cHeightU32 = rowsU32 * 26 + 2; const colorTable = cividis.RGBA32; const barCode = new Uint32Array(8); const contextU8 = DOM.context2d(width, cHeightU8, 1); const contextU32 = DOM.context2d(width, cHeightU32, 1); const imageDataU8 = contextU8.createImageData(width, cHeightU8); const imageDataU32 = contextU32.createImageData(width, cHeightU32); const pixels32U8 = new Uint32Array(imageDataU8.data.buffer); const pixels32U32 = new Uint32Array(imageDataU32.data.buffer); pixels32U8.fill(isLittleEndian ? 0xFF000000 : 0xFF); pixels32U32.fill(isLittleEndian ? 0xFF000000 : 0xFF); for(let i = 0; i < bufferU8.length; i++){ const ywU8 = (2 + ((i / columns8) | 0) * 26) * width; const xU8 = 1 + ((i % columns8) * 24); const idxU8 = xU8 + ywU8; const ywU32 = (2 + ((i / columns32) | 0) * 26) * width; const ixU32 = i % columns32; const xU32 = 1 + (ixU32 * 23) + ((ixU32 >>> 2) << 2); const idxU32 = xU32 + ywU32; const val8 = bufferU8[i]; const val32 = (bufferU32[i>>>2] >>> ((3 - (i&3))*8)) & 0xFF; let color = colorTable[val8]; for (let cx = 1; cx < 23; cx++){ for (let cy = 1; cy < 23; cy++){ pixels32U8[idxU8 + cx + cy * width] = color; } } for(let j = 0; j < 8; j++){ barCode[j] = colorTable[((val8 >> (7 - j)) & 1) * 0xD0 + 0x18]; } for (let cx = 4; cx < 20; cx++){ color = barCode[(cx - 4)>>1]; pixels32U8[idxU8 + cx + 18 * width] = color; pixels32U8[idxU8 + cx + 19 * width] = color; pixels32U8[idxU8 + cx + 20 * width] = color; } color = colorTable[val32]; for (let cx = 1; cx < 23; cx++){ for (let cy = 1; cy < 23; cy++){ pixels32U32[idxU32 + cx + cy * width] = color; } } for(let j = 0; j < 8; j++){ barCode[j] = colorTable[((val32 >> (7 - j)) & 1) * 0xD0 + 0x18]; } for (let cx = 4; cx < 20; cx++){ color = barCode[(cx - 4)>>1]; pixels32U32[idxU32 + cx + 18 * width] = color; pixels32U32[idxU32 + cx + 19 * width] = color; pixels32U32[idxU32 + cx + 20 * width] = color; } } contextU8.putImageData(imageDataU8, 0, 0); contextU32.putImageData(imageDataU32, 0, 0); return { contextU8, contextU32 }; }