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

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <errno.h>
   5 #include "csgray.h"
   6
   7 static int save_image(const char *fname, float *pix, int xsz, int ysz);
   8 static int parse_opt(int argc, char **argv);
   9
  10 static int width = 800, height = 600;
  11 static const char *out_fname = "output.ppm";
  12
  13 int main(int argc, char **argv)
  14 {
  15         csg_object *oa, *ob, *oc, *lt;
  16         float *pixels;
  17
  18         if(parse_opt(argc, argv) == -1) {
  19                 return 1;
  20         }
  21
  22         if(csg_init() == -1) {
  23                 return 1;
  24         }
  25
  26         if(!(pixels = malloc(width * height * 3 * sizeof *pixels))) {
  27                 perror("failed to allocate framebuffer");
  28                 return 1;
  29         }
  30
  31         csg_view(0, 0, 5, 0, 0, 0);
  32
  33         oa = csg_sphere(0, 0, 0, 1);
  34         csg_color(oa, 1, 0, 0);
  35         ob = csg_sphere(-0.3, 0.7, 0.7, 0.7);
  36         csg_color(ob, 0, 0, 1);
  37         oc = csg_union(oa, ob);
  38         csg_add_object(oc);
  39
  40         lt = csg_null(-4, 10, 20);
  41         csg_emission(lt, 1, 1, 1);
  42         csg_add_object(lt);
  43
  44         csg_render_image(pixels, width, height);
  45         save_image(out_fname, pixels, width, height);
  46
  47         csg_destroy();
  48         return 0;
  49 }
  50
  51 static int save_image(const char *fname, float *pix, int xsz, int ysz)
  52 {
  53         int i;
  54         FILE *fp;
  55
  56         if(!(fp = fopen(fname, "wb"))) {
  57                 fprintf(stderr, "failed to open %s for writing: %s\n", fname, strerror(errno));
  58                 return -1;
  59         }
  60
  61         fprintf(fp, "P6\n%d %d\n65535\n", xsz, ysz);
  62
  63         for(i=0; i<xsz * ysz; i++) {
  64                 unsigned int r = *pix++ * 65535.0f;
  65                 unsigned int g = *pix++ * 65535.0f;
  66                 unsigned int b = *pix++ * 65535.0f;
  67
  68                 if(r > 0xffff) r = 0xffff;
  69                 if(g > 0xffff) g = 0xffff;
  70                 if(b > 0xffff) b = 0xffff;
  71
  72                 fputc(r >> 8, fp);
  73                 fputc(r, fp);
  74                 fputc(g >> 8, fp);
  75                 fputc(g, fp);
  76                 fputc(b >> 8, fp);
  77                 fputc(b, fp);
  78         }
  79         fclose(fp);
  80         return 0;
  81 }
  82
  83 static void print_usage(const char *argv0)
  84 {
  85         printf("Usage: %s [options] <csg file>\n", argv0);
  86         printf("Options:\n");
  87         printf(" -s <WxH>  output image resolution\n");
  88         printf(" -o <file> output image file\n");
  89         printf(" -h        print usage information and exit\n");
  90 }
  91
  92 static int parse_opt(int argc, char **argv)
  93 {
  94         int i;
  95
  96         for(i=1; i<argc; i++) {
  97                 if(argv[i][0] == '-') {
  98                         if(argv[i][2] == 0) {
  99                                 switch(argv[i][1]) {
 100                                 case 's':
 101                                         if(sscanf(argv[++i], "%dx%d", &width, &height) != 2) {
 102                                                 fprintf(stderr, "-s must be followed by WIDTHxHEIGHT\n");
 103                                                 return -1;
 104                                         }
 105                                         break;
 106
 107                                 case 'o':
 108                                         out_fname = argv[++i];
 109                                         break;
 110
 111                                 case 'h':
 112                                         print_usage(argv[0]);
 113                                         exit(0);
 114
 115                                 default:
 116                                         fprintf(stderr, "invalid option: %s\n", argv[i]);
 117                                         return -1;
 118                                 }
 119                         } else {
 120                                 fprintf(stderr, "invalid option: %s\n", argv[i]);
 121                                 return -1;
 122                         }
 123                 } else {
 124                         fprintf(stderr, "unexpected argument: %s\n", argv[i]);
 125                         return -1;
 126                 }
 127         }
 128         return 0;
 129 }