class PixelData { static unpack(array, {height=8, width=8, stacked=false}={}) { let bit = 0n, idx = 0; const values = new Uint8Array(height * width); const unpacked = [ ]; array.forEach((packed, k) => { idx = 0; for(let row=0; row d3.range(this.width).reduce((sum,col) => sum + this.at(row,col), 0); const colSum = col => d3.range(this.height).reduce((sum,row) => sum + this.at(row,col), 0); let left,right,top,bottom; for(top=0; top < this.height; ++top) if(rowSum(top)) break; for(bottom=this.height-1; bottom >= 0; --bottom) if(rowSum(bottom)) break; for(left=0; left < this.width; ++left) if(colSum(left)) break; for(right=this.width-1; right >= 0; --right) if(colSum(right)) break; const height = bottom - top + 1, width = right - left + 1; //console.log([left,right,width], [top,bottom,height]); if(height == this.height && width == this.width) return this; const values = new Uint8Array(height * width); for(let row = top; row <= bottom; ++row) { for(let col = left; col <= right; ++col) { values[(row - top) * width + (col - left)] = this.at(row, col); } } return new PixelData(height, width, values); } isEqualTo(other) { if(other.width != this.width || other.height != this.height) return false; for(let row = 0; row < this.height; ++row) { for(let col = 0; col < this.width; ++col) { if(other.at(row,col) != this.at(row,col)) return false; } } return true; } pack(array, {idx=0, dx=0, dy=0}) { if(this.width > 8 || this.height > 8) throw new Error(`Cannot pack ${this.height} x ${this.width} pixels`); array[idx] = 0n; let bit = 0n; for(let row=0; row < this.height; ++row) { for(let col=0; col < this.width; ++col) { if(this.at(row, col)) array[idx] |= 1n << BigInt(8 * (row+dy) + col + dx); } } return array; } }