1 24c02865 2005-01-04 devnull /*
  2 24c02865 2005-01-04 devnull  * rotate an image 180° in O(log Dx + log Dy) /dev/draw writes,
  3 24c02865 2005-01-04 devnull  * using an extra buffer same size as the image.
  4 fa325e9b 2020-01-10 cross  *
  5 24c02865 2005-01-04 devnull  * the basic concept is that you can invert an array by inverting
  6 24c02865 2005-01-04 devnull  * the top half, inverting the bottom half, and then swapping them.
  7 24c02865 2005-01-04 devnull  * the code does this slightly backwards to ensure O(log n) runtime.
  8 24c02865 2005-01-04 devnull  * (If you do it wrong, you can get O(log² n) runtime.)
  9 fa325e9b 2020-01-10 cross  *
 10 24c02865 2005-01-04 devnull  * This is usually overkill, but it speeds up slow remote
 11 24c02865 2005-01-04 devnull  * connections quite a bit.
 12 24c02865 2005-01-04 devnull  */
 13 24c02865 2005-01-04 devnull 
 14 24c02865 2005-01-04 devnull #include <u.h>
 15 24c02865 2005-01-04 devnull #include <libc.h>
 16 24c02865 2005-01-04 devnull #include <bio.h>
 17 24c02865 2005-01-04 devnull #include <draw.h>
 18 05a4d855 2007-03-26 devnull #include <thread.h>
 19 17157e4a 2006-03-20 devnull #include <cursor.h>
 20 24c02865 2005-01-04 devnull #include "page.h"
 21 24c02865 2005-01-04 devnull 
 22 24c02865 2005-01-04 devnull int ndraw = 0;
 23 24c02865 2005-01-04 devnull enum {
 24 24c02865 2005-01-04 devnull 	Xaxis = 0,
 25 05a4d855 2007-03-26 devnull 	Yaxis = 1,
 26 24c02865 2005-01-04 devnull };
 27 24c02865 2005-01-04 devnull 
 28 24c02865 2005-01-04 devnull Image *mtmp;
 29 24c02865 2005-01-04 devnull 
 30 24c02865 2005-01-04 devnull void
 31 24c02865 2005-01-04 devnull writefile(char *name, Image *im, int gran)
 32 24c02865 2005-01-04 devnull {
 33 24c02865 2005-01-04 devnull 	static int c = 100;
 34 24c02865 2005-01-04 devnull 	int fd;
 35 24c02865 2005-01-04 devnull 	char buf[200];
 36 24c02865 2005-01-04 devnull 
 37 24c02865 2005-01-04 devnull 	snprint(buf, sizeof buf, "%d%s%d", c++, name, gran);
 38 24c02865 2005-01-04 devnull 	fd = create(buf, OWRITE, 0666);
 39 24c02865 2005-01-04 devnull 	if(fd < 0)
 40 fa325e9b 2020-01-10 cross 		return;
 41 24c02865 2005-01-04 devnull 	writeimage(fd, im, 0);
 42 24c02865 2005-01-04 devnull 	close(fd);
 43 24c02865 2005-01-04 devnull }
 44 24c02865 2005-01-04 devnull 
 45 24c02865 2005-01-04 devnull void
 46 24c02865 2005-01-04 devnull moveup(Image *im, Image *tmp, int a, int b, int c, int axis)
 47 24c02865 2005-01-04 devnull {
 48 24c02865 2005-01-04 devnull 	Rectangle range;
 49 24c02865 2005-01-04 devnull 	Rectangle dr0, dr1;
 50 24c02865 2005-01-04 devnull 	Point p0, p1;
 51 24c02865 2005-01-04 devnull 
 52 24c02865 2005-01-04 devnull 	if(a == b || b == c)
 53 24c02865 2005-01-04 devnull 		return;
 54 24c02865 2005-01-04 devnull 
 55 24c02865 2005-01-04 devnull 	drawop(tmp, tmp->r, im, nil, im->r.min, S);
 56 24c02865 2005-01-04 devnull 
 57 24c02865 2005-01-04 devnull 	switch(axis){
 58 24c02865 2005-01-04 devnull 	case Xaxis:
 59 24c02865 2005-01-04 devnull 		range = Rect(a, im->r.min.y,  c, im->r.max.y);
 60 24c02865 2005-01-04 devnull 		dr0 = range;
 61 24c02865 2005-01-04 devnull 		dr0.max.x = dr0.min.x+(c-b);
 62 24c02865 2005-01-04 devnull 		p0 = Pt(b, im->r.min.y);
 63 24c02865 2005-01-04 devnull 
 64 24c02865 2005-01-04 devnull 		dr1 = range;
 65 24c02865 2005-01-04 devnull 		dr1.min.x = dr1.max.x-(b-a);
 66 24c02865 2005-01-04 devnull 		p1 = Pt(a, im->r.min.y);
 67 24c02865 2005-01-04 devnull 		break;
 68 24c02865 2005-01-04 devnull 	case Yaxis:
 69 05a4d855 2007-03-26 devnull 	default:
 70 24c02865 2005-01-04 devnull 		range = Rect(im->r.min.x, a,  im->r.max.x, c);
 71 24c02865 2005-01-04 devnull 		dr0 = range;
 72 24c02865 2005-01-04 devnull 		dr0.max.y = dr0.min.y+(c-b);
 73 24c02865 2005-01-04 devnull 		p0 = Pt(im->r.min.x, b);
 74 24c02865 2005-01-04 devnull 
 75 24c02865 2005-01-04 devnull 		dr1 = range;
 76 24c02865 2005-01-04 devnull 		dr1.min.y = dr1.max.y-(b-a);
 77 24c02865 2005-01-04 devnull 		p1 = Pt(im->r.min.x, a);
 78 24c02865 2005-01-04 devnull 		break;
 79 24c02865 2005-01-04 devnull 	}
 80 24c02865 2005-01-04 devnull 	drawop(im, dr0, tmp, nil, p0, S);
 81 24c02865 2005-01-04 devnull 	drawop(im, dr1, tmp, nil, p1, S);
 82 24c02865 2005-01-04 devnull }
 83 24c02865 2005-01-04 devnull 
 84 24c02865 2005-01-04 devnull void
 85 24c02865 2005-01-04 devnull interlace(Image *im, Image *tmp, int axis, int n, Image *mask, int gran)
 86 24c02865 2005-01-04 devnull {
 87 24c02865 2005-01-04 devnull 	Point p0, p1;
 88 220c15d2 2012-10-20 rsc 	Rectangle r0;
 89 24c02865 2005-01-04 devnull 
 90 24c02865 2005-01-04 devnull 	r0 = im->r;
 91 24c02865 2005-01-04 devnull 	switch(axis) {
 92 24c02865 2005-01-04 devnull 	case Xaxis:
 93 24c02865 2005-01-04 devnull 		r0.max.x = n;
 94 24c02865 2005-01-04 devnull 		p0 = (Point){gran, 0};
 95 24c02865 2005-01-04 devnull 		p1 = (Point){-gran, 0};
 96 24c02865 2005-01-04 devnull 		break;
 97 24c02865 2005-01-04 devnull 	case Yaxis:
 98 05a4d855 2007-03-26 devnull 	default:
 99 24c02865 2005-01-04 devnull 		r0.max.y = n;
100 24c02865 2005-01-04 devnull 		p0 = (Point){0, gran};
101 24c02865 2005-01-04 devnull 		p1 = (Point){0, -gran};
102 24c02865 2005-01-04 devnull 		break;
103 24c02865 2005-01-04 devnull 	}
104 24c02865 2005-01-04 devnull 
105 24c02865 2005-01-04 devnull 	drawop(tmp, im->r, im, display->opaque, im->r.min, S);
106 24c02865 2005-01-04 devnull 	gendrawop(im, r0, tmp, p0, mask, mask->r.min, S);
107 24c02865 2005-01-04 devnull 	gendrawop(im, r0, tmp, p1, mask, p1, S);
108 24c02865 2005-01-04 devnull }
109 24c02865 2005-01-04 devnull 
110 24c02865 2005-01-04 devnull /*
111 24c02865 2005-01-04 devnull  * Halve the grating period in the mask.
112 fa325e9b 2020-01-10 cross  * The grating currently looks like
113 24c02865 2005-01-04 devnull  * ####____####____####____####____
114 24c02865 2005-01-04 devnull  * where #### is opacity.
115 24c02865 2005-01-04 devnull  *
116 24c02865 2005-01-04 devnull  * We want
117 24c02865 2005-01-04 devnull  * ##__##__##__##__##__##__##__##__
118 24c02865 2005-01-04 devnull  * which is achieved by shifting the mask
119 24c02865 2005-01-04 devnull  * and drawing on itself through itself.
120 fa325e9b 2020-01-10 cross  * Draw doesn't actually allow this, so
121 24c02865 2005-01-04 devnull  * we have to copy it first.
122 24c02865 2005-01-04 devnull  *
123 24c02865 2005-01-04 devnull  *     ####____####____####____####____ (dst)
124 24c02865 2005-01-04 devnull  * +   ____####____####____####____#### (src)
125 24c02865 2005-01-04 devnull  * in  __####____####____####____####__ (mask)
126 24c02865 2005-01-04 devnull  * ===========================================
127 24c02865 2005-01-04 devnull  *     ##__##__##__##__##__##__##__##__
128 24c02865 2005-01-04 devnull  */
129 24c02865 2005-01-04 devnull int
130 24c02865 2005-01-04 devnull nextmask(Image *mask, int axis, int maskdim)
131 24c02865 2005-01-04 devnull {
132 05a4d855 2007-03-26 devnull 	Point o;
133 24c02865 2005-01-04 devnull 
134 05a4d855 2007-03-26 devnull 	o = axis==Xaxis ? Pt(maskdim,0) : Pt(0,maskdim);
135 24c02865 2005-01-04 devnull 	drawop(mtmp, mtmp->r, mask, nil, mask->r.min, S);
136 05a4d855 2007-03-26 devnull 	gendrawop(mask, mask->r, mtmp, o, mtmp, divpt(o,-2), S);
137 05a4d855 2007-03-26 devnull //	writefile("mask", mask, maskdim/2);
138 24c02865 2005-01-04 devnull 	return maskdim/2;
139 24c02865 2005-01-04 devnull }
140 24c02865 2005-01-04 devnull 
141 24c02865 2005-01-04 devnull void
142 24c02865 2005-01-04 devnull shuffle(Image *im, Image *tmp, int axis, int n, Image *mask, int gran,
143 24c02865 2005-01-04 devnull 	int lastnn)
144 24c02865 2005-01-04 devnull {
145 24c02865 2005-01-04 devnull 	int nn, left;
146 24c02865 2005-01-04 devnull 
147 24c02865 2005-01-04 devnull 	if(gran == 0)
148 24c02865 2005-01-04 devnull 		return;
149 24c02865 2005-01-04 devnull 	left = n%(2*gran);
150 24c02865 2005-01-04 devnull 	nn = n - left;
151 24c02865 2005-01-04 devnull 
152 24c02865 2005-01-04 devnull 	interlace(im, tmp, axis, nn, mask, gran);
153 05a4d855 2007-03-26 devnull //	writefile("interlace", im, gran);
154 fa325e9b 2020-01-10 cross 
155 24c02865 2005-01-04 devnull 	gran = nextmask(mask, axis, gran);
156 24c02865 2005-01-04 devnull 	shuffle(im, tmp, axis, n, mask, gran, nn);
157 05a4d855 2007-03-26 devnull //	writefile("shuffle", im, gran);
158 24c02865 2005-01-04 devnull 	moveup(im, tmp, lastnn, nn, n, axis);
159 05a4d855 2007-03-26 devnull //	writefile("move", im, gran);
160 24c02865 2005-01-04 devnull }
161 24c02865 2005-01-04 devnull 
162 24c02865 2005-01-04 devnull void
163 24c02865 2005-01-04 devnull rot180(Image *im)
164 24c02865 2005-01-04 devnull {
165 24c02865 2005-01-04 devnull 	Image *tmp, *tmp0;
166 24c02865 2005-01-04 devnull 	Image *mask;
167 24c02865 2005-01-04 devnull 	Rectangle rmask;
168 24c02865 2005-01-04 devnull 	int gran;
169 24c02865 2005-01-04 devnull 
170 24c02865 2005-01-04 devnull 	if(chantodepth(im->chan) < 8){
171 24c02865 2005-01-04 devnull 		/* this speeds things up dramatically; draw is too slow on sub-byte pixel sizes */
172 24c02865 2005-01-04 devnull 		tmp0 = xallocimage(display, im->r, CMAP8, 0, DNofill);
173 24c02865 2005-01-04 devnull 		drawop(tmp0, tmp0->r, im, nil, im->r.min, S);
174 24c02865 2005-01-04 devnull 	}else
175 24c02865 2005-01-04 devnull 		tmp0 = im;
176 24c02865 2005-01-04 devnull 
177 24c02865 2005-01-04 devnull 	tmp = xallocimage(display, tmp0->r, tmp0->chan, 0, DNofill);
178 24c02865 2005-01-04 devnull 	if(tmp == nil){
179 24c02865 2005-01-04 devnull 		if(tmp0 != im)
180 24c02865 2005-01-04 devnull 			freeimage(tmp0);
181 24c02865 2005-01-04 devnull 		return;
182 24c02865 2005-01-04 devnull 	}
183 24c02865 2005-01-04 devnull 	for(gran=1; gran<Dx(im->r); gran *= 2)
184 24c02865 2005-01-04 devnull 		;
185 24c02865 2005-01-04 devnull 	gran /= 4;
186 24c02865 2005-01-04 devnull 
187 24c02865 2005-01-04 devnull 	rmask.min = ZP;
188 24c02865 2005-01-04 devnull 	rmask.max = (Point){2*gran, 100};
189 24c02865 2005-01-04 devnull 
190 24c02865 2005-01-04 devnull 	mask = xallocimage(display, rmask, GREY1, 1, DTransparent);
191 24c02865 2005-01-04 devnull 	mtmp = xallocimage(display, rmask, GREY1, 1, DTransparent);
192 24c02865 2005-01-04 devnull 	if(mask == nil || mtmp == nil) {
193 24c02865 2005-01-04 devnull 		fprint(2, "out of memory during rot180: %r\n");
194 24c02865 2005-01-04 devnull 		wexits("memory");
195 24c02865 2005-01-04 devnull 	}
196 24c02865 2005-01-04 devnull 	rmask.max.x = gran;
197 24c02865 2005-01-04 devnull 	drawop(mask, rmask, display->opaque, nil, ZP, S);
198 05a4d855 2007-03-26 devnull //	writefile("mask", mask, gran);
199 24c02865 2005-01-04 devnull 	shuffle(im, tmp, Xaxis, Dx(im->r), mask, gran, 0);
200 24c02865 2005-01-04 devnull 	freeimage(mask);
201 24c02865 2005-01-04 devnull 	freeimage(mtmp);
202 24c02865 2005-01-04 devnull 
203 24c02865 2005-01-04 devnull 	for(gran=1; gran<Dy(im->r); gran *= 2)
204 24c02865 2005-01-04 devnull 		;
205 24c02865 2005-01-04 devnull 	gran /= 4;
206 24c02865 2005-01-04 devnull 	rmask.max = (Point){100, 2*gran};
207 24c02865 2005-01-04 devnull 	mask = xallocimage(display, rmask, GREY1, 1, DTransparent);
208 24c02865 2005-01-04 devnull 	mtmp = xallocimage(display, rmask, GREY1, 1, DTransparent);
209 24c02865 2005-01-04 devnull 	if(mask == nil || mtmp == nil) {
210 24c02865 2005-01-04 devnull 		fprint(2, "out of memory during rot180: %r\n");
211 24c02865 2005-01-04 devnull 		wexits("memory");
212 24c02865 2005-01-04 devnull 	}
213 24c02865 2005-01-04 devnull 	rmask.max.y = gran;
214 24c02865 2005-01-04 devnull 	drawop(mask, rmask, display->opaque, nil, ZP, S);
215 24c02865 2005-01-04 devnull 	shuffle(im, tmp, Yaxis, Dy(im->r), mask, gran, 0);
216 24c02865 2005-01-04 devnull 	freeimage(mask);
217 24c02865 2005-01-04 devnull 	freeimage(mtmp);
218 24c02865 2005-01-04 devnull 	freeimage(tmp);
219 24c02865 2005-01-04 devnull 	if(tmp0 != im)
220 24c02865 2005-01-04 devnull 		freeimage(tmp0);
221 24c02865 2005-01-04 devnull }
222 24c02865 2005-01-04 devnull 
223 24c02865 2005-01-04 devnull /* rotates an image 90 degrees clockwise */
224 24c02865 2005-01-04 devnull Image *
225 24c02865 2005-01-04 devnull rot90(Image *im)
226 24c02865 2005-01-04 devnull {
227 24c02865 2005-01-04 devnull 	Image *tmp;
228 24c02865 2005-01-04 devnull 	int i, j, dx, dy;
229 24c02865 2005-01-04 devnull 
230 24c02865 2005-01-04 devnull 	dx = Dx(im->r);
231 24c02865 2005-01-04 devnull 	dy = Dy(im->r);
232 24c02865 2005-01-04 devnull 	tmp = xallocimage(display, Rect(0, 0, dy, dx), im->chan, 0, DCyan);
233 24c02865 2005-01-04 devnull 	if(tmp == nil) {
234 24c02865 2005-01-04 devnull 		fprint(2, "out of memory during rot90: %r\n");
235 24c02865 2005-01-04 devnull 		wexits("memory");
236 24c02865 2005-01-04 devnull 	}
237 24c02865 2005-01-04 devnull 
238 24c02865 2005-01-04 devnull 	for(j = 0; j < dx; j++) {
239 24c02865 2005-01-04 devnull 		for(i = 0; i < dy; i++) {
240 24c02865 2005-01-04 devnull 			drawop(tmp, Rect(i, j, i+1, j+1), im, nil, Pt(j, dy-(i+1)), S);
241 24c02865 2005-01-04 devnull 		}
242 24c02865 2005-01-04 devnull 	}
243 24c02865 2005-01-04 devnull 	freeimage(im);
244 24c02865 2005-01-04 devnull 
245 24c02865 2005-01-04 devnull 	return(tmp);
246 24c02865 2005-01-04 devnull }
247 24c02865 2005-01-04 devnull 
248 17157e4a 2006-03-20 devnull /* rotates an image 270 degrees clockwise */
249 17157e4a 2006-03-20 devnull Image *
250 17157e4a 2006-03-20 devnull rot270(Image *im)
251 17157e4a 2006-03-20 devnull {
252 17157e4a 2006-03-20 devnull 	Image *tmp;
253 17157e4a 2006-03-20 devnull 	int i, j, dx, dy;
254 17157e4a 2006-03-20 devnull 
255 17157e4a 2006-03-20 devnull 	dx = Dx(im->r);
256 17157e4a 2006-03-20 devnull 	dy = Dy(im->r);
257 17157e4a 2006-03-20 devnull 	tmp = xallocimage(display, Rect(0, 0, dy, dx), im->chan, 0, DCyan);
258 17157e4a 2006-03-20 devnull 	if(tmp == nil) {
259 17157e4a 2006-03-20 devnull 		fprint(2, "out of memory during rot270: %r\n");
260 17157e4a 2006-03-20 devnull 		wexits("memory");
261 17157e4a 2006-03-20 devnull 	}
262 17157e4a 2006-03-20 devnull 
263 17157e4a 2006-03-20 devnull 	for(i = 0; i < dy; i++) {
264 17157e4a 2006-03-20 devnull 		for(j = 0; j < dx; j++) {
265 17157e4a 2006-03-20 devnull 			drawop(tmp, Rect(i, j, i+1, j+1), im, nil, Pt(dx-(j+1), i), S);
266 17157e4a 2006-03-20 devnull 		}
267 17157e4a 2006-03-20 devnull 	}
268 17157e4a 2006-03-20 devnull 	freeimage(im);
269 17157e4a 2006-03-20 devnull 
270 17157e4a 2006-03-20 devnull 	return(tmp);
271 17157e4a 2006-03-20 devnull }
272 17157e4a 2006-03-20 devnull 
273 24c02865 2005-01-04 devnull /* from resample.c -- resize from → to using interpolation */
274 24c02865 2005-01-04 devnull 
275 24c02865 2005-01-04 devnull 
276 24c02865 2005-01-04 devnull #define K2 7	/* from -.7 to +.7 inclusive, meaning .2 into each adjacent pixel */
277 24c02865 2005-01-04 devnull #define NK (2*K2+1)
278 24c02865 2005-01-04 devnull double K[NK];
279 24c02865 2005-01-04 devnull 
280 24c02865 2005-01-04 devnull double
281 24c02865 2005-01-04 devnull fac(int L)
282 24c02865 2005-01-04 devnull {
283 24c02865 2005-01-04 devnull 	int i, f;
284 24c02865 2005-01-04 devnull 
285 24c02865 2005-01-04 devnull 	f = 1;
286 24c02865 2005-01-04 devnull 	for(i=L; i>1; --i)
287 24c02865 2005-01-04 devnull 		f *= i;
288 24c02865 2005-01-04 devnull 	return f;
289 24c02865 2005-01-04 devnull }
290 24c02865 2005-01-04 devnull 
291 fa325e9b 2020-01-10 cross /*
292 24c02865 2005-01-04 devnull  * i0(x) is the modified Bessel function, Σ (x/2)^2L / (L!)²
293 24c02865 2005-01-04 devnull  * There are faster ways to calculate this, but we precompute
294 24c02865 2005-01-04 devnull  * into a table so let's keep it simple.
295 24c02865 2005-01-04 devnull  */
296 24c02865 2005-01-04 devnull double
297 24c02865 2005-01-04 devnull i0(double x)
298 24c02865 2005-01-04 devnull {
299 24c02865 2005-01-04 devnull 	double v;
300 24c02865 2005-01-04 devnull 	int L;
301 24c02865 2005-01-04 devnull 
302 24c02865 2005-01-04 devnull 	v = 1.0;
303 24c02865 2005-01-04 devnull 	for(L=1; L<10; L++)
304 24c02865 2005-01-04 devnull 		v += pow(x/2., 2*L)/pow(fac(L), 2);
305 24c02865 2005-01-04 devnull 	return v;
306 24c02865 2005-01-04 devnull }
307 24c02865 2005-01-04 devnull 
308 24c02865 2005-01-04 devnull double
309 05a4d855 2007-03-26 devnull kaiser(double x, double t, double a)
310 24c02865 2005-01-04 devnull {
311 05a4d855 2007-03-26 devnull 	if(fabs(x) > t)
312 24c02865 2005-01-04 devnull 		return 0.;
313 05a4d855 2007-03-26 devnull 	return i0(a*sqrt(1-(x*x/(t*t))))/i0(a);
314 24c02865 2005-01-04 devnull }
315 24c02865 2005-01-04 devnull 
316 17157e4a 2006-03-20 devnull 
317 24c02865 2005-01-04 devnull void
318 24c02865 2005-01-04 devnull resamplex(uchar *in, int off, int d, int inx, uchar *out, int outx)
319 24c02865 2005-01-04 devnull {
320 24c02865 2005-01-04 devnull 	int i, x, k;
321 24c02865 2005-01-04 devnull 	double X, xx, v, rat;
322 24c02865 2005-01-04 devnull 
323 24c02865 2005-01-04 devnull 
324 24c02865 2005-01-04 devnull 	rat = (double)inx/(double)outx;
325 24c02865 2005-01-04 devnull 	for(x=0; x<outx; x++){
326 24c02865 2005-01-04 devnull 		if(inx == outx){
327 24c02865 2005-01-04 devnull 			/* don't resample if size unchanged */
328 24c02865 2005-01-04 devnull 			out[off+x*d] = in[off+x*d];
329 24c02865 2005-01-04 devnull 			continue;
330 24c02865 2005-01-04 devnull 		}
331 24c02865 2005-01-04 devnull 		v = 0.0;
332 24c02865 2005-01-04 devnull 		X = x*rat;
333 24c02865 2005-01-04 devnull 		for(k=-K2; k<=K2; k++){
334 24c02865 2005-01-04 devnull 			xx = X + rat*k/10.;
335 24c02865 2005-01-04 devnull 			i = xx;
336 24c02865 2005-01-04 devnull 			if(i < 0)
337 24c02865 2005-01-04 devnull 				i = 0;
338 24c02865 2005-01-04 devnull 			if(i >= inx)
339 24c02865 2005-01-04 devnull 				i = inx-1;
340 24c02865 2005-01-04 devnull 			v += in[off+i*d] * K[K2+k];
341 24c02865 2005-01-04 devnull 		}
342 24c02865 2005-01-04 devnull 		out[off+x*d] = v;
343 24c02865 2005-01-04 devnull 	}
344 24c02865 2005-01-04 devnull }
345 24c02865 2005-01-04 devnull 
346 24c02865 2005-01-04 devnull void
347 24c02865 2005-01-04 devnull resampley(uchar **in, int off, int iny, uchar **out, int outy)
348 24c02865 2005-01-04 devnull {
349 24c02865 2005-01-04 devnull 	int y, i, k;
350 24c02865 2005-01-04 devnull 	double Y, yy, v, rat;
351 24c02865 2005-01-04 devnull 
352 24c02865 2005-01-04 devnull 	rat = (double)iny/(double)outy;
353 24c02865 2005-01-04 devnull 	for(y=0; y<outy; y++){
354 24c02865 2005-01-04 devnull 		if(iny == outy){
355 24c02865 2005-01-04 devnull 			/* don't resample if size unchanged */
356 24c02865 2005-01-04 devnull 			out[y][off] = in[y][off];
357 24c02865 2005-01-04 devnull 			continue;
358 24c02865 2005-01-04 devnull 		}
359 24c02865 2005-01-04 devnull 		v = 0.0;
360 24c02865 2005-01-04 devnull 		Y = y*rat;
361 24c02865 2005-01-04 devnull 		for(k=-K2; k<=K2; k++){
362 24c02865 2005-01-04 devnull 			yy = Y + rat*k/10.;
363 24c02865 2005-01-04 devnull 			i = yy;
364 24c02865 2005-01-04 devnull 			if(i < 0)
365 24c02865 2005-01-04 devnull 				i = 0;
366 24c02865 2005-01-04 devnull 			if(i >= iny)
367 24c02865 2005-01-04 devnull 				i = iny-1;
368 24c02865 2005-01-04 devnull 			v += in[i][off] * K[K2+k];
369 24c02865 2005-01-04 devnull 		}
370 24c02865 2005-01-04 devnull 		out[y][off] = v;
371 24c02865 2005-01-04 devnull 	}
372 24c02865 2005-01-04 devnull 
373 24c02865 2005-01-04 devnull }
374 24c02865 2005-01-04 devnull 
375 24c02865 2005-01-04 devnull Image*
376 24c02865 2005-01-04 devnull resample(Image *from, Image *to)
377 24c02865 2005-01-04 devnull {
378 24c02865 2005-01-04 devnull 	int i, j, bpl, nchan;
379 24c02865 2005-01-04 devnull 	uchar **oscan, **nscan;
380 24c02865 2005-01-04 devnull 	char tmp[20];
381 24c02865 2005-01-04 devnull 	int xsize, ysize;
382 24c02865 2005-01-04 devnull 	double v;
383 24c02865 2005-01-04 devnull 	Image *t1, *t2;
384 24c02865 2005-01-04 devnull 	ulong tchan;
385 24c02865 2005-01-04 devnull 
386 24c02865 2005-01-04 devnull 	for(i=-K2; i<=K2; i++){
387 24c02865 2005-01-04 devnull 		K[K2+i] = kaiser(i/10., K2/10., 4.);
388 24c02865 2005-01-04 devnull 	}
389 24c02865 2005-01-04 devnull 
390 24c02865 2005-01-04 devnull 	/* normalize */
391 24c02865 2005-01-04 devnull 	v = 0.0;
392 24c02865 2005-01-04 devnull 	for(i=0; i<NK; i++)
393 24c02865 2005-01-04 devnull 		v += K[i];
394 24c02865 2005-01-04 devnull 	for(i=0; i<NK; i++)
395 24c02865 2005-01-04 devnull 		K[i] /= v;
396 24c02865 2005-01-04 devnull 
397 24c02865 2005-01-04 devnull 	switch(from->chan){
398 24c02865 2005-01-04 devnull 	case GREY8:
399 24c02865 2005-01-04 devnull 	case RGB24:
400 24c02865 2005-01-04 devnull 	case RGBA32:
401 24c02865 2005-01-04 devnull 	case ARGB32:
402 24c02865 2005-01-04 devnull 	case XRGB32:
403 24c02865 2005-01-04 devnull 		break;
404 24c02865 2005-01-04 devnull 
405 24c02865 2005-01-04 devnull 	case CMAP8:
406 24c02865 2005-01-04 devnull 	case RGB15:
407 24c02865 2005-01-04 devnull 	case RGB16:
408 24c02865 2005-01-04 devnull 		tchan = RGB24;
409 24c02865 2005-01-04 devnull 		goto Convert;
410 24c02865 2005-01-04 devnull 
411 24c02865 2005-01-04 devnull 	case GREY1:
412 24c02865 2005-01-04 devnull 	case GREY2:
413 24c02865 2005-01-04 devnull 	case GREY4:
414 24c02865 2005-01-04 devnull 		tchan = GREY8;
415 24c02865 2005-01-04 devnull 	Convert:
416 24c02865 2005-01-04 devnull 		/* use library to convert to byte-per-chan form, then convert back */
417 24c02865 2005-01-04 devnull 		t1 = xallocimage(display, Rect(0, 0, Dx(from->r), Dy(from->r)), tchan, 0, DNofill);
418 24c02865 2005-01-04 devnull 		if(t1 == nil) {
419 24c02865 2005-01-04 devnull 			fprint(2, "out of memory for temp image 1 in resample: %r\n");
420 24c02865 2005-01-04 devnull 			wexits("memory");
421 24c02865 2005-01-04 devnull 		}
422 24c02865 2005-01-04 devnull 		drawop(t1, t1->r, from, nil, ZP, S);
423 24c02865 2005-01-04 devnull 		t2 = xallocimage(display, to->r, tchan, 0, DNofill);
424 24c02865 2005-01-04 devnull 		if(t2 == nil) {
425 24c02865 2005-01-04 devnull 			fprint(2, "out of memory temp image 2 in resample: %r\n");
426 24c02865 2005-01-04 devnull 			wexits("memory");
427 24c02865 2005-01-04 devnull 		}
428 24c02865 2005-01-04 devnull 		resample(t1, t2);
429 24c02865 2005-01-04 devnull 		drawop(to, to->r, t2, nil, ZP, S);
430 24c02865 2005-01-04 devnull 		freeimage(t1);
431 24c02865 2005-01-04 devnull 		freeimage(t2);
432 24c02865 2005-01-04 devnull 		return to;
433 24c02865 2005-01-04 devnull 
434 24c02865 2005-01-04 devnull 	default:
435 24c02865 2005-01-04 devnull 		sysfatal("can't handle channel type %s", chantostr(tmp, from->chan));
436 24c02865 2005-01-04 devnull 	}
437 24c02865 2005-01-04 devnull 
438 24c02865 2005-01-04 devnull 	xsize = Dx(to->r);
439 24c02865 2005-01-04 devnull 	ysize = Dy(to->r);
440 24c02865 2005-01-04 devnull 	oscan = malloc(Dy(from->r)*sizeof(uchar*));
441 24c02865 2005-01-04 devnull 	nscan = malloc(max(ysize, Dy(from->r))*sizeof(uchar*));
442 24c02865 2005-01-04 devnull 	if(oscan == nil || nscan == nil)
443 24c02865 2005-01-04 devnull 		sysfatal("can't allocate: %r");
444 24c02865 2005-01-04 devnull 
445 24c02865 2005-01-04 devnull 	/* unload original image into scan lines */
446 24c02865 2005-01-04 devnull 	bpl = bytesperline(from->r, from->depth);
447 24c02865 2005-01-04 devnull 	for(i=0; i<Dy(from->r); i++){
448 24c02865 2005-01-04 devnull 		oscan[i] = malloc(bpl);
449 24c02865 2005-01-04 devnull 		if(oscan[i] == nil)
450 24c02865 2005-01-04 devnull 			sysfatal("can't allocate: %r");
451 24c02865 2005-01-04 devnull 		j = unloadimage(from, Rect(from->r.min.x, from->r.min.y+i, from->r.max.x, from->r.min.y+i+1), oscan[i], bpl);
452 24c02865 2005-01-04 devnull 		if(j != bpl)
453 24c02865 2005-01-04 devnull 			sysfatal("unloadimage");
454 24c02865 2005-01-04 devnull 	}
455 24c02865 2005-01-04 devnull 
456 24c02865 2005-01-04 devnull 	/* allocate scan lines for destination. we do y first, so need at least Dy(from->r) lines */
457 24c02865 2005-01-04 devnull 	bpl = bytesperline(Rect(0, 0, xsize, Dy(from->r)), from->depth);
458 24c02865 2005-01-04 devnull 	for(i=0; i<max(ysize, Dy(from->r)); i++){
459 24c02865 2005-01-04 devnull 		nscan[i] = malloc(bpl);
460 24c02865 2005-01-04 devnull 		if(nscan[i] == nil)
461 24c02865 2005-01-04 devnull 			sysfatal("can't allocate: %r");
462 24c02865 2005-01-04 devnull 	}
463 24c02865 2005-01-04 devnull 
464 24c02865 2005-01-04 devnull 	/* resample in X */
465 24c02865 2005-01-04 devnull 	nchan = from->depth/8;
466 24c02865 2005-01-04 devnull 	for(i=0; i<Dy(from->r); i++){
467 24c02865 2005-01-04 devnull 		for(j=0; j<nchan; j++){
468 24c02865 2005-01-04 devnull 			if(j==0 && from->chan==XRGB32)
469 24c02865 2005-01-04 devnull 				continue;
470 24c02865 2005-01-04 devnull 			resamplex(oscan[i], j, nchan, Dx(from->r), nscan[i], xsize);
471 24c02865 2005-01-04 devnull 		}
472 24c02865 2005-01-04 devnull 		free(oscan[i]);
473 24c02865 2005-01-04 devnull 		oscan[i] = nscan[i];
474 24c02865 2005-01-04 devnull 		nscan[i] = malloc(bpl);
475 24c02865 2005-01-04 devnull 		if(nscan[i] == nil)
476 24c02865 2005-01-04 devnull 			sysfatal("can't allocate: %r");
477 24c02865 2005-01-04 devnull 	}
478 24c02865 2005-01-04 devnull 
479 24c02865 2005-01-04 devnull 	/* resample in Y */
480 24c02865 2005-01-04 devnull 	for(i=0; i<xsize; i++)
481 24c02865 2005-01-04 devnull 		for(j=0; j<nchan; j++)
482 24c02865 2005-01-04 devnull 			resampley(oscan, nchan*i+j, Dy(from->r), nscan, ysize);
483 24c02865 2005-01-04 devnull 
484 24c02865 2005-01-04 devnull 	/* pack data into destination */
485 24c02865 2005-01-04 devnull 	bpl = bytesperline(to->r, from->depth);
486 24c02865 2005-01-04 devnull 	for(i=0; i<ysize; i++){
487 24c02865 2005-01-04 devnull 		j = loadimage(to, Rect(0, i, xsize, i+1), nscan[i], bpl);
488 24c02865 2005-01-04 devnull 		if(j != bpl)
489 24c02865 2005-01-04 devnull 			sysfatal("loadimage: %r");
490 24c02865 2005-01-04 devnull 	}
491 24c02865 2005-01-04 devnull 
492 24c02865 2005-01-04 devnull 	for(i=0; i<Dy(from->r); i++){
493 24c02865 2005-01-04 devnull 		free(oscan[i]);
494 24c02865 2005-01-04 devnull 		free(nscan[i]);
495 24c02865 2005-01-04 devnull 	}
496 24c02865 2005-01-04 devnull 	free(oscan);
497 24c02865 2005-01-04 devnull 	free(nscan);
498 24c02865 2005-01-04 devnull 
499 24c02865 2005-01-04 devnull 	return to;
500 24c02865 2005-01-04 devnull }