git.mutantstargoat.com Git - csgray/blob - src/main.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <math.h>
   5 #include <errno.h>
   6 #include "csgray.h"
   7
   8 #define DFL_WIDTH       800
   9 #define DFL_HEIGHT      600
  10 #define DFL_GAMMA       2.2f
  11 #define DFL_OUTFILE     "output.ppm"
  12
  13 static int save_image(const char *fname, float *pix, int xsz, int ysz);
  14 static int parse_opt(int argc, char **argv);
  15
  16 static int width = DFL_WIDTH, height = DFL_HEIGHT;
  17 static float inv_gamma = 1.0f / DFL_GAMMA;
  18 static const char *out_fname = DFL_OUTFILE;
  19 static const char *in_fname;
  20
  21 int main(int argc, char **argv)
  22 {
  23         csg_object *oa, *ob, *oc, *obj;
  24         float *pixels;
  25
  26         if(parse_opt(argc, argv) == -1) {
  27                 return 1;
  28         }
  29
  30         if(csg_init() == -1) {
  31                 return 1;
  32         }
  33
  34         if(csg_load(in_fname) == -1) {
  35                 return 1;
  36         }
  37
  38         if(!(pixels = malloc(width * height * 3 * sizeof *pixels))) {
  39                 perror("failed to allocate framebuffer");
  40                 return 1;
  41         }
  42
  43         /*
  44         csg_view(0, 0, 5, 0, 0, 0);
  45
  46         oa = csg_sphere(0, 0, 0, 1);
  47         csg_color(oa, 1, 0.1, 0.05);
  48         csg_roughness(oa, 0.3);
  49         ob = csg_sphere(0.3, 0.7, 0.7, 0.7);
  50         csg_color(ob, 0.2, 0.3, 1);
  51         csg_roughness(ob, 0.3);
  52         oc = csg_subtraction(oa, ob);
  53
  54         oa = oc;
  55
  56         ob = csg_sphere(-0.9, -0.1, 0.7, 0.5);
  57         csg_color(ob, 1, 0.9, 0.2);
  58         csg_roughness(ob, 0.3);
  59
  60         oc = csg_subtraction(oa, ob);
  61
  62         csg_add_object(oc);
  63
  64         obj = csg_plane(0, -1, 0, 0, 1, 0);
  65         csg_color(obj, 0.4, 0.7, 0.4);
  66         csg_add_object(obj);
  67
  68         obj = csg_null(-4, 10, 10);
  69         csg_emission(obj, 80, 80, 80);
  70         csg_add_object(obj);
  71         */
  72
  73         csg_render_image(pixels, width, height);
  74         save_image(out_fname, pixels, width, height);
  75
  76         csg_destroy();
  77         return 0;
  78 }
  79
  80 static int save_image(const char *fname, float *pix, int xsz, int ysz)
  81 {
  82         int i;
  83         FILE *fp;
  84
  85         if(!(fp = fopen(fname, "wb"))) {
  86                 fprintf(stderr, "failed to open %s for writing: %s\n", fname, strerror(errno));
  87                 return -1;
  88         }
  89
  90         fprintf(fp, "P6\n%d %d\n255\n", xsz, ysz);
  91
  92         for(i=0; i<xsz * ysz; i++) {
  93                 unsigned int r = pow(*pix++, inv_gamma) * 255.0f;
  94                 unsigned int g = pow(*pix++, inv_gamma) * 255.0f;
  95                 unsigned int b = pow(*pix++, inv_gamma) * 255.0f;
  96
  97                 if(r > 255) r = 255;
  98                 if(g > 255) g = 255;
  99                 if(b > 255) b = 255;
 100
 101                 fputc(r, fp);
 102                 fputc(g, fp);
 103                 fputc(b, fp);
 104         }
 105         fclose(fp);
 106         return 0;
 107 }
 108
 109 static void print_usage(const char *argv0)
 110 {
 111         printf("Usage: %s [options] <csg file>\n", argv0);
 112         printf("Options:\n");
 113         printf(" -s <WxH>   output image resolution (default: %dx%d)\n", DFL_WIDTH, DFL_HEIGHT);
 114         printf(" -g <gamma> set output gamma (default: %g)\n", DFL_GAMMA);
 115         printf(" -o <file>  output image file (default: %s)\n", DFL_OUTFILE);
 116         printf(" -h         print usage information and exit\n");
 117 }
 118
 119 static int parse_opt(int argc, char **argv)
 120 {
 121         int i;
 122
 123         for(i=1; i<argc; i++) {
 124                 if(argv[i][0] == '-') {
 125                         if(argv[i][2] == 0) {
 126                                 switch(argv[i][1]) {
 127                                 case 's':
 128                                         if(sscanf(argv[++i], "%dx%d", &width, &height) != 2) {
 129                                                 fprintf(stderr, "-s must be followed by WIDTHxHEIGHT\n");
 130                                                 return -1;
 131                                         }
 132                                         break;
 133
 134                                 case 'g':
 135                                         if((inv_gamma = atof(argv[++i])) == 0.0f) {
 136                                                 fprintf(stderr, "-g must be followed by a non-zero gamma value\n");
 137                                                 return -1;
 138                                         }
 139                                         inv_gamma = 1.0f / inv_gamma;
 140                                         break;
 141
 142                                 case 'o':
 143                                         out_fname = argv[++i];
 144                                         break;
 145
 146                                 case 'h':
 147                                         print_usage(argv[0]);
 148                                         exit(0);
 149
 150                                 default:
 151                                         fprintf(stderr, "invalid option: %s\n", argv[i]);
 152                                         return -1;
 153                                 }
 154                         } else {
 155                                 fprintf(stderr, "invalid option: %s\n", argv[i]);
 156                                 return -1;
 157                         }
 158                 } else {
 159                         if(in_fname) {
 160                                 fprintf(stderr, "unexpected argument: %s\n", argv[i]);
 161                                 return -1;
 162                         }
 163                         in_fname = argv[i];
 164                 }
 165         }
 166
 167         if(!in_fname) {
 168                 fprintf(stderr, "you need to pass a scene file to read\n");
 169                 return -1;
 170         }
 171
 172         return 0;
 173 }