X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=libs%2Fimago%2Fsrc%2Fconv.c;fp=libs%2Fimago%2Fsrc%2Fconv.c;h=61fe54c44617608e67f16d899d103c74158b1314;hb=d5f45e3128c537f272615cf76242e1dfebccdee7;hp=0000000000000000000000000000000000000000;hpb=dd7ce87b0ad2b8a1b4758bcc9354e993b71c8599;p=raydungeon

diff --git a/libs/imago/src/conv.c b/libs/imago/src/conv.c
new file mode 100644
index 0000000..61fe54c
--- /dev/null
+++ b/libs/imago/src/conv.c
@@ -0,0 +1,370 @@
+/*
+libimago - a multi-format image file input/output library.
+Copyright (C) 2010-2021 John Tsiombikas <nuclear@member.fsf.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published
+by the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#include <string.h>
+#include "imago2.h"
+#include "byteord.h"
+
+/* pixel-format conversions are sub-optimal at the moment to avoid
+ * writing a lot of code. optimize at some point ?
+ */
+
+#define CLAMP(x, a, b)	((x) < (a) ? (a) : ((x) > (b) ? (b) : (x)))
+
+struct pixel {
+	float r, g, b, a;
+};
+
+static void unpack_grey8(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap);
+static void unpack_rgb24(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap);
+static void unpack_rgba32(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap);
+static void unpack_bgra32(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap);
+static void unpack_greyf(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap);
+static void unpack_rgbf(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap);
+static void unpack_rgbaf(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap);
+static void unpack_rgb565(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap);
+static void unpack_idx8(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap);
+
+static void pack_grey8(void *pptr, struct pixel *unp, int count);
+static void pack_rgb24(void *pptr, struct pixel *unp, int count);
+static void pack_rgba32(void *pptr, struct pixel *unp, int count);
+static void pack_bgra32(void *pptr, struct pixel *unp, int count);
+static void pack_greyf(void *pptr, struct pixel *unp, int count);
+static void pack_rgbf(void *pptr, struct pixel *unp, int count);
+static void pack_rgbaf(void *pptr, struct pixel *unp, int count);
+static void pack_rgb565(void *pptr, struct pixel *unp, int count);
+
+/* XXX keep in sync with enum img_fmt at imago2.h */
+static void (*unpack[])(struct pixel*, void*, int, struct img_colormap*) = {
+	unpack_grey8,
+	unpack_rgb24,
+	unpack_rgba32,
+	unpack_greyf,
+	unpack_rgbf,
+	unpack_rgbaf,
+	unpack_bgra32,
+	unpack_rgb565,
+	unpack_idx8
+};
+
+/* XXX keep in sync with enum img_fmt at imago2.h */
+static void (*pack[])(void*, struct pixel*, int) = {
+	pack_grey8,
+	pack_rgb24,
+	pack_rgba32,
+	pack_greyf,
+	pack_rgbf,
+	pack_rgbaf,
+	pack_bgra32,
+	pack_rgb565,
+	0
+};
+
+
+int img_convert(struct img_pixmap *img, enum img_fmt tofmt)
+{
+	struct pixel pbuf[8];
+	int bufsz = (img->width & 7) == 0 ? 8 : ((img->width & 3) == 0 ? 4 : 1);
+	int i, num_pix = img->width * img->height;
+	int num_iter = num_pix / bufsz;
+	char *sptr, *dptr;
+	struct img_pixmap nimg;
+	struct img_colormap *cmap = img_colormap(img);
+
+	if(img->fmt == tofmt) {
+		return 0;	/* nothing to do */
+	}
+
+	if(tofmt == IMG_FMT_IDX8) {
+		/* TODO */
+		fprintf(stderr, "imago: conversions to indexed not implemented yet\n");
+		return 0;
+	}
+
+	img_init(&nimg);
+	if(img_set_pixels(&nimg, img->width, img->height, tofmt, 0) == -1) {
+		img_destroy(&nimg);
+		return -1;
+	}
+
+	sptr = img->pixels;
+	dptr = nimg.pixels;
+
+	for(i=0; i<num_iter; i++) {
+		unpack[img->fmt](pbuf, sptr, bufsz, cmap);
+		pack[tofmt](dptr, pbuf, bufsz);
+
+		sptr += bufsz * img->pixelsz;
+		dptr += bufsz * nimg.pixelsz;
+	}
+
+	img_copy(img, &nimg);
+	img_destroy(&nimg);
+	return 0;
+}
+
+/* the following functions *could* benefit from SIMD */
+
+static void unpack_grey8(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap)
+{
+	int i;
+	unsigned char *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		unp->r = unp->g = unp->b = (float)*pix++ / 255.0;
+		unp->a = 1.0;
+		unp++;
+	}
+}
+
+static void unpack_rgb24(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap)
+{
+	int i;
+	unsigned char *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		unp->r = (float)*pix++ / 255.0;
+		unp->g = (float)*pix++ / 255.0;
+		unp->b = (float)*pix++ / 255.0;
+		unp->a = 1.0;
+		unp++;
+	}
+}
+
+static void unpack_rgba32(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap)
+{
+	int i;
+	unsigned char *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		unp->r = (float)*pix++ / 255.0;
+		unp->g = (float)*pix++ / 255.0;
+		unp->b = (float)*pix++ / 255.0;
+		unp->a = (float)*pix++ / 255.0;
+		unp++;
+	}
+}
+
+static void unpack_bgra32(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap)
+{
+	int i;
+	unsigned char *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		unp->a = (float)*pix++ / 255.0;
+		unp->r = (float)*pix++ / 255.0;
+		unp->g = (float)*pix++ / 255.0;
+		unp->b = (float)*pix++ / 255.0;
+		unp++;
+	}
+}
+
+static void unpack_greyf(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap)
+{
+	int i;
+	float *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		unp->r = unp->g = unp->b = *pix++;
+		unp->a = 1.0;
+		unp++;
+	}
+}
+
+static void unpack_rgbf(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap)
+{
+	int i;
+	float *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		unp->r = *pix++;
+		unp->g = *pix++;
+		unp->b = *pix++;
+		unp->a = 1.0;
+		unp++;
+	}
+}
+
+static void unpack_rgbaf(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap)
+{
+	int i;
+	float *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		unp->r = *pix++;
+		unp->g = *pix++;
+		unp->b = *pix++;
+		unp->a = *pix++;
+		unp++;
+	}
+}
+
+static void unpack_rgb565(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap)
+{
+	int i;
+	uint16_t *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		uint16_t r, g, b, p = *pix++;
+		b = (p & 0x1f) << 3;
+		if(b & 8) b |= 7;	/* fill LSbits with whatever bit 0 was */
+		g = (p >> 2) & 0xfc;
+		if(g & 4) g |= 3;	/* ditto */
+		r = (p >> 8) & 0xf8;
+		if(r & 8) r |= 7;	/* same */
+
+		unp->r = (float)r / 255.0f;
+		unp->g = (float)g / 255.0f;
+		unp->b = (float)b / 255.0f;
+		unp->a = 1.0f;
+		unp++;
+	}
+}
+
+static void unpack_idx8(struct pixel *unp, void *pptr, int count, struct img_colormap *cmap)
+{
+	int i, idx;
+	unsigned char *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		idx = *pix++;
+		if(idx >= cmap->ncolors) {
+			unp->r = unp->g = unp->b = 0;
+		} else {
+			unp->r = (float)cmap->color[idx].r / 255.0f;
+			unp->g = (float)cmap->color[idx].g / 255.0f;
+			unp->b = (float)cmap->color[idx].b / 255.0f;
+		}
+		unp->a = 1.0f;
+		unp++;
+	}
+}
+
+
+static void pack_grey8(void *pptr, struct pixel *unp, int count)
+{
+	int i;
+	unsigned char *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		int lum = (int)(255.0 * (unp->r + unp->g + unp->b) / 3.0);
+		*pix++ = CLAMP(lum, 0, 255);
+		unp++;
+	}
+}
+
+static void pack_rgb24(void *pptr, struct pixel *unp, int count)
+{
+	int i;
+	unsigned char *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		int r = (int)(unp->r * 255.0);
+		int g = (int)(unp->g * 255.0);
+		int b = (int)(unp->b * 255.0);
+
+		*pix++ = CLAMP(r, 0, 255);
+		*pix++ = CLAMP(g, 0, 255);
+		*pix++ = CLAMP(b, 0, 255);
+		unp++;
+	}
+}
+
+static void pack_rgba32(void *pptr, struct pixel *unp, int count)
+{
+	int i;
+	unsigned char *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		int r = (int)(unp->r * 255.0);
+		int g = (int)(unp->g * 255.0);
+		int b = (int)(unp->b * 255.0);
+		int a = (int)(unp->a * 255.0);
+
+		*pix++ = CLAMP(r, 0, 255);
+		*pix++ = CLAMP(g, 0, 255);
+		*pix++ = CLAMP(b, 0, 255);
+		*pix++ = CLAMP(a, 0, 255);
+		unp++;
+	}
+}
+
+static void pack_bgra32(void *pptr, struct pixel *unp, int count)
+{
+	int i;
+	unsigned char *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		int r = (int)(unp->r * 255.0);
+		int g = (int)(unp->g * 255.0);
+		int b = (int)(unp->b * 255.0);
+		int a = (int)(unp->a * 255.0);
+
+		*pix++ = CLAMP(b, 0, 255);
+		*pix++ = CLAMP(g, 0, 255);
+		*pix++ = CLAMP(r, 0, 255);
+		*pix++ = CLAMP(a, 0, 255);
+		unp++;
+	}
+}
+
+static void pack_greyf(void *pptr, struct pixel *unp, int count)
+{
+	int i;
+	float *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		*pix++ = (unp->r + unp->g + unp->b) / 3.0;
+		unp++;
+	}
+}
+
+static void pack_rgbf(void *pptr, struct pixel *unp, int count)
+{
+	int i;
+	float *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		*pix++ = unp->r;
+		*pix++ = unp->g;
+		*pix++ = unp->b;
+		unp++;
+	}
+}
+
+static void pack_rgbaf(void *pptr, struct pixel *unp, int count)
+{
+	memcpy(pptr, unp, count * sizeof *unp);
+}
+
+
+static void pack_rgb565(void *pptr, struct pixel *unp, int count)
+{
+	int i;
+	uint16_t *pix = pptr;
+
+	for(i=0; i<count; i++) {
+		uint16_t r = (uint16_t)(unp->r * 31.0f);
+		uint16_t g = (uint16_t)(unp->g * 63.0f);
+		uint16_t b = (uint16_t)(unp->b * 31.0f);
+		if(r > 31) r = 31;
+		if(g > 63) g = 63;
+		if(b > 31) b = 31;
+		*pix++ = (r << 11) | (g << 5) | b;
+		unp++;
+	}
+}