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!7 import java.awt.geom.*; p { BufferedImage img = loadBufferedImage(#1006973); BWImage bw = getAlphaChannel(img); Image2B alpha = new Image2B(bw); int w = alpha.w(), h = alpha.h(); Path2D.Float path = new Path2D.Float(); int x = w/2; int y = -1; while (y < h && !isInteresting(getQuadrant(alpha, x, y))) ++y; int x1 = x, y1 = y; path.moveTo(x, y); new HashSet<Pt> seen; while (seen.add(new Pt(x, y))) { int q = getQuadrant(alpha, x, y); Pt next = null; for (Pt p : neighborhood(x, y)) if (!seen.contains(p) && isInteresting(getQuadrant(alpha, p.x, p.y))) { next = p; break; } if (next == null) break; x = next.x; y = next.y; path.lineTo(x, y); } print("Have " + n(seen, "points")); showImage(alpha); showImage(renderShape(path, w, h)); } sbool isInteresting(int q) { ret q != 0 && q != 0x1111; } static int getQuadrant(Image2B img, int x, int y) { ret (getQuadrant_getPixel(img, x, y) ? 0x1000 : 0) + (getQuadrant_getPixel(img, x+1, y) ? 0x0100 : 0) + (getQuadrant_getPixel(img, x, y+1) ? 0x0010 : 0) + (getQuadrant_getPixel(img, x+1, y+1) ? 0x0001 : 0); } static bool getQuadrant_getPixel(Image2B img, int x, int y) { ret x >= 0 && x < img.w && y >= 0 && y < img.h && img.getPixel(x, y); } static L<Pt> neighborhood(int x, int y) { ret ll(new Pt(x-1, y-1), new Pt(x, y-1), new Pt(x+1, y-1), new Pt(x-1, y), new Pt(x+1, y), new Pt(x-1, y+1), new Pt(x, y+1), new Pt(x+1, y+1)); }
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Travelled to 13 computer(s): aoiabmzegqzx, bhatertpkbcr, cbybwowwnfue, cfunsshuasjs, gwrvuhgaqvyk, ishqpsrjomds, lpdgvwnxivlt, mqqgnosmbjvj, pyentgdyhuwx, pzhvpgtvlbxg, tslmcundralx, tvejysmllsmz, vouqrxazstgt
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Snippet ID: | #1006978 |
Snippet name: | Make Shape from image's alpha channel (for drawing transparent windows) [dev.] |
Eternal ID of this version: | #1006978/16 |
Text MD5: | 5d5f1f0cccdbc20da642cda7e6cbd19f |
Transpilation MD5: | 7986b747dbf706d4faa7d1b3494e55b9 |
Author: | stefan |
Category: | javax / imaging |
Type: | JavaX source code |
Public (visible to everyone): | Yes |
Archived (hidden from active list): | No |
Created/modified: | 2017-02-21 19:55:30 |
Source code size: | 1595 bytes / 64 lines |
Pitched / IR pitched: | No / No |
Views / Downloads: | 463 / 615 |
Version history: | 15 change(s) |
Referenced in: | #1006981 - alphaToShape - quite experimental shape generation from alpha channel |