primary rays without jitter

[cyberay] / src / rt.c

diff --git a/src/rt.c b/src/rt.c
index 2c6ceaf..0ad8a7c 100644 (file)
--- a/src/rt.c
+++ b/src/rt.c
@@ -1,6 +1,14 @@
 #include "rt.h"
 
 struct framebuffer fb;
+struct thread_pool *tpool;
+float view_xform[16];
+float vfov = M_PI / 4;
+
+static float aspect;
+
+static void ray_trace(cgm_vec3 *color, cgm_ray *ray);
+static void primary_ray(cgm_ray *ray, int x, int y, int sample);
 
 int fbsize(int width, int height)
 {
@@ -14,24 +22,43 @@ int fbsize(int width, int height)
        fb.pixels = tmp;
        fb.width = width;
        fb.height = height;
+
+       aspect = (float)fb.width / (float)fb.height;
+
        return 0;
 }
 
 void render(void)
 {
        int i, j;
+       cgm_ray ray;
        cgm_vec3 *fbptr = fb.pixels;
 
        for(i=0; i<fb.height; i++) {
                for(j=0; j<fb.width; j++) {
-                       if(i < 3 || i >= fb.height - 3 || j < 3 || j >= fb.width - 3) {
-                               fbptr->x = 1.0f;
-                               fbptr->y = fbptr->z = 0.0f;
-                       } else {
-                               fbptr->x = fbptr->z = 0.0f;
-                               fbptr->y = 1.0f;
-                       }
+                       primary_ray(&ray, j, i, 0);
+                       ray_trace(fbptr, &ray);
                        fbptr++;
                }
        }
 }
+
+static void ray_trace(cgm_vec3 *color, cgm_ray *ray)
+{
+       color->x = ray->dir.x * 0.5f + 0.5f;
+       color->y = ray->dir.y * 0.5f + 0.5f;
+       color->z = 0.0f;
+}
+
+static void primary_ray(cgm_ray *ray, int x, int y, int sample)
+{
+       ray->origin.x = ray->origin.y = ray->origin.z = 0.0f;
+       ray->dir.x = (2.0f * (float)x / (float)fb.width - 1.0f) * aspect;
+       ray->dir.y = 1.0f - 2.0f * (float)y / (float)fb.height;
+       ray->dir.z = -1.0f / tan(vfov / 2.0f);
+       cgm_vnormalize(&ray->dir);
+
+       /* TODO jitter */
+
+       cgm_rmul_mr(ray, view_xform);
+}