34 lines
1005 B
JavaScript
34 lines
1005 B
JavaScript
//draws a line between two points on canvas
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function line(x0,y0,x1,y1, brushSize) {
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var dx = Math.abs(x1-x0);
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var dy = Math.abs(y1-y0);
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var sx = (x0 < x1 ? 1 : -1);
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var sy = (y0 < y1 ? 1 : -1);
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var err = dx-dy;
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while (true) {
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//set pixel
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// If the current tool is the brush
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if (currentTool.name == 'pencil' || currentTool.name == 'rectangle' || currentTool.name == 'ellipse') {
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// I fill the rect
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currentLayer.context.fillRect(x0-Math.floor(brushSize/2), y0-Math.floor(brushSize/2), brushSize, brushSize);
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} else if (currentTool.name == 'eraser') {
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// In case I'm using the eraser I must clear the rect
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currentLayer.context.clearRect(x0-Math.floor(tool.eraser.brushSize/2), y0-Math.floor(tool.eraser.brushSize/2), tool.eraser.brushSize, tool.eraser.brushSize);
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}
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//if we've reached the end goal, exit the loop
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if ((x0==x1) && (y0==y1)) break;
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var e2 = 2*err;
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if (e2 >-dy) {
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err -=dy;
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x0+=sx;
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}
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if (e2 < dx) {
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err +=dx;
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y0+=sy;
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}
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}
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} |