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75d0b8fe04
I added the experimental folder to show some work on filters that
can be applied to an entire layer. Multiple filters can be applied
to a layer (in any order, multiple times). To hook into the layer I
use:
layer.on('draw', filterFunc);
Eventually, I would like to move that to `layer.filterFunc` and
automatically apply it after the draw. `filterFunc` looks like:
function filterFunc(){
// Get pixel data and create a temporary pixel buffer for working
var imageData = this.getContext().getImageData(0,0,this.getCanvas().width,this.getCanvas().height);
var scratchData = this.getContext().createImageData(imageData);
// Apply all filters here
ColorStretch(imageData,scratchData,{});
// Copy the pixel data back
this.getContext().putImageData(scratchData,0,0);
}
`ColorStretch` is an example of a filter. It takes 3 arguments: the
original image data, image data to write the result to, and an options
object.
42 lines
1.2 KiB
JavaScript
42 lines
1.2 KiB
JavaScript
FlipX = (function () {
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var FlipX = function (src, dst, opt) {
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var srcPixels = src.data,
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dstPixels = dst.data,
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xSize = src.width,
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ySize = src.height,
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i, m, x, y;
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for (x = 0; x < xSize; x += 1) {
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for (y = 0; y < ySize; y += 1) {
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i = (y * xSize + x) * 4; // original
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m = ((y + 1) * xSize - x) * 4; // flipped
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dstPixels[m + 0] = srcPixels[i + 0];
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dstPixels[m + 1] = srcPixels[i + 1];
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dstPixels[m + 2] = srcPixels[i + 2];
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dstPixels[m + 3] = srcPixels[i + 3];
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}
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}
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};
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return FlipX;
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})();
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FlipY = (function () {
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var FlipY = function (src, dst, opt) {
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var srcPixels = src.data,
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dstPixels = dst.data,
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xSize = src.width,
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ySize = src.height,
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i, m, x, y;
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for (x = 0; x < xSize; x += 1) {
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for (y = 0; y < ySize; y += 1) {
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i = (y * xSize + x) * 4; // original
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m = ((ySize - y) * xSize + x) * 4; // flipped
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dstPixels[m + 0] = srcPixels[i + 0];
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dstPixels[m + 1] = srcPixels[i + 1];
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dstPixels[m + 2] = srcPixels[i + 2];
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dstPixels[m + 3] = srcPixels[i + 3];
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}
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}
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};
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return FlipY;
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})();
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