# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1333804032 -10800
# Node ID ae10631bb11b45b2c0b515437f75d132059ad21d
# Parent  f40e4edfee7e1ee1c2f8192e9e3f707d88c57c82
cleaning up a bit to expand

diff -r f40e4edfee7e -r ae10631bb11b .hgignore
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/.hgignore	Sat Apr 07 16:07:12 2012 +0300
@@ -0,0 +1,5 @@
+^volray$
+\.o$
+\.d$
+\.swp$
+^data
diff -r f40e4edfee7e -r ae10631bb11b src/volume.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/volume.c	Sat Apr 07 16:07:12 2012 +0300
@@ -0,0 +1,162 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+#ifndef __APPLE__
+#include <GL/gl.h>
+#else
+#include <OpenGL/gl.h>
+#endif
+
+#include <imago2.h>
+
+struct slice {
+	char *name;
+	struct slice *next;
+};
+
+static struct slice *read_voldesc(const char *fname, struct volume *vol);
+static char *trim(char *str);
+
+struct volume *load_volume(const char *fname)
+{
+	struct slice *slist;
+	struct volume *vol = 0;
+
+	if(!(vol = malloc(sizeof *vol))) {
+		perror("failed to allocate volume");
+		return 0;
+	}
+	memset(vol, 0, sizeof *vol);
+	vol->zaspect = 1;
+
+	if(!(slist = read_voldesc(fname, vol))) {
+		goto err;
+	}
+
+	glGenTextures(1, &vol->tex_vol);
+	glBindTexture(GL_TEXTURE_3D, vol->tex_vol);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
+
+	for(i=0; i<vol->sz[2]; i++) {
+		struct img_pixmap img;
+		struct slice *slice = head;
+		head = head->next;
+
+		img_init(&img);
+		if(img_load(&img, slice->name) == -1) {
+			fprintf(stderr, "failed to load volume slice: %s\n", slice->name);
+			goto err;
+		}
+	}
+
+	glGenTextures(1, &vol->tex_grad);
+	glBindTexture(GL_TEXTURE_3D, vol->tex_grad);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
+
+err:
+	while(slist) {
+		struct slice *tmp = slist;
+		slist = slist->next;
+		free(tmp->name);
+		free(tmp);
+	}
+	if(vol) {
+		if(vol->tex_vol)
+			glDeleteTextures(1, &vol->tex_vol);
+		if(vol->tex_grad)
+			glDeleteTextures(1, &vol->tex_grad);
+		free(vol);
+	}
+	return 0;
+}
+
+static struct slice *read_voldesc(const char *fname, struct volume *vol)
+{
+	FILE *fp = 0;
+	char buf[512];
+	int mode_slices = 0;
+	struct slice *head = 0, *tail;
+
+	if(!(fp = fopen(fname, "r"))) {
+		fprintf(stderr, "failed to open volume descriptor: %s\n", fname);
+		return 0;
+	}
+	fgets(buf, sizeof buf, fp);
+	if(strstr(buf, "VOLDESC") != buf) {
+		fprintf(stderr, "invalid file format while trying to read volume descriptor: %s\n", fname);
+		goto err;
+	}
+
+	while(fgets(buf, sizeof buf, fp)) {
+		char *line = trim(buf);
+
+		if(!*line || *line == '#')
+			continue;
+
+		if(mode_slices) {
+			/* we're in the part that contains filenames... append to the list */
+			struct slice *node = malloc(sizeof *node);
+			if(!node || !(node->name = malloc(strlen(line) + 1))) {
+				perror("failed to allocate list node");
+				free(node);
+				goto err;
+			}
+			strcpy(node->name, line);
+			node->next = 0;
+
+			if(head) {
+				tail->next = node;
+				tail = node;
+			} else {
+				head = tail = node;
+			}
+			vol->sz[2]++;
+		} else {
+			/* TODO we're in the options part... parse */
+		}
+	}
+	fclose(fp);
+
+	if(!vol->sz[2]) {
+		fprintf(stderr, "file: %s contains no slices\n", fname);
+		goto err;
+	}
+
+	return head;
+
+err:
+	while(head) {
+		struct slice *tmp = head;
+		head = head->next;
+		free(tmp->name);
+		free(tmp);
+	}
+	if(fp) {
+		fclose(fp);
+	}
+	return 0;
+}
+
+static char *trim(char *str)
+{
+	char *tmp = str + strlen(str) - 1;
+
+	while(isspace(*tmp))
+		tmp--;
+	tmp[1] = 0;
+
+	tmp = str;
+	while(isspace(*tmp))
+		tmp++;
+	return tmp;
+}
diff -r f40e4edfee7e -r ae10631bb11b src/volume.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/volume.h	Sat Apr 07 16:07:12 2012 +0300
@@ -0,0 +1,15 @@
+#ifndef VOLUME_H_
+#define VOLUME_H_
+
+#include <stdint.h>
+
+struct volume {
+	int sz[3];
+	float zaspect;
+	unsigned int tex_vol, tex_grad;
+};
+
+struct volume *load_volume(const char *fname);
+void free_volume(struct volume *vol);
+
+#endif	/* VOLUME_H_ */
diff -r f40e4edfee7e -r ae10631bb11b volray.p.glsl
--- a/volray.p.glsl	Thu Apr 05 00:52:11 2012 +0300
+++ b/volray.p.glsl	Sat Apr 07 16:07:12 2012 +0300
@@ -63,15 +63,14 @@
 		vec3 pos = ray.origin + ray.dir * t;
 		t += ray_step;
 
-		float val = eval(pos) * energy;
+		float val = eval(pos);
 		vec3 norm;
 
 		norm.x = eval(pos + vec3(OFFS, 0.0, 0.0)) - val;
 		norm.y = eval(pos + vec3(0.0, OFFS, 0.0)) - val;
 		norm.z = eval(pos + vec3(0.0, 0.0, OFFS)) - val;
-		norm = normalize(norm);
 
-		col += shade(ray, pos, norm) * val;
+		col += shade(ray, pos, normalize(norm)) * val * energy;
 		energy -= val;
 		if(energy < 0.001) {
 			break;
@@ -84,15 +83,15 @@
 
 vec3 shade(Ray ray, vec3 pos, vec3 norm)
 {
-	vec3 ldir = normalize(vec3(10.0, 10.0, -10.0) - pos);
+	vec3 ldir = -pos;//normalize(vec3(10.0, 10.0, -10.0) - pos);
 	vec3 vdir = -ray.dir;
 	vec3 hdir = normalize(ldir + vdir);
 
 	float ndotl = dot(ldir, norm);
 	float ndoth = dot(hdir, norm);
 
-	vec3 dcol = vec3(1.0, 1.0, 1.0) * max(ndotl, 0.0);
-	vec3 scol = vec3(0.6, 0.6, 0.6) * pow(max(ndoth, 0.0), 50.0);
+	vec3 dcol = vec3(0.9, 0.9, 0.9) * max(ndotl, 0.0);
+	vec3 scol = vec3(0.5, 0.5, 0.5) * pow(max(ndoth, 0.0), 50.0);
 
 	return vec3(0.01, 0.01, 0.01) + dcol + scol;
 }