added cylinder primitive

[csgray] / src / csgray.c

diff --git a/src/csgray.c b/src/csgray.c
index 150f5fb..ae0f8ad 100644 (file)
--- a/src/csgray.c
+++ b/src/csgray.c
@@ -44,12 +44,30 @@ void csg_destroy(void)
 
 void csg_view(float x, float y, float z, float tx, float ty, float tz)
 {
+       float dir[3];
+       float len;
+
        cam.x = x;
        cam.y = y;
        cam.z = z;
        cam.tx = tx;
        cam.ty = ty;
        cam.tz = tz;
+
+       dir[0] = tx - x;
+       dir[1] = ty - y;
+       dir[2] = tz - z;
+       len = sqrt(dir[0] * dir[0] + dir[1] * dir[1] + dir[2] * dir[2]);
+
+       if(1.0f - fabs(ty - y) / len < 1e-6f) {
+               cam.ux = cam.uy = 0.0f;
+               cam.uz = -1.0f;
+       } else {
+               cam.ux = cam.uz = 0.0f;
+               cam.uy = 1.0f;
+       }
+
+       mat4_lookat(cam.xform, x, y, z, tx, ty, tz, cam.ux, cam.uy, cam.uz);
 }
 
 void csg_fov(float fov)
@@ -135,10 +153,12 @@ int csg_remove_object(csg_object *o)
 
 void csg_free_object(csg_object *o)
 {
-       if(o->ob.destroy) {
-               o->ob.destroy(o);
+       if(o) {
+               if(o->ob.destroy) {
+                       o->ob.destroy(o);
+               }
+               free(o);
        }
-       free(o);
 }
 
 static union csg_object *alloc_object(int type)
@@ -169,6 +189,7 @@ csg_object *csg_null(float x, float y, float z)
        }
 
        mat4_translation(o->ob.xform, x, y, z);
+       mat4_translation(o->ob.inv_xform, -x, -y, -z);
        return o;
 }
 
@@ -182,25 +203,27 @@ csg_object *csg_sphere(float x, float y, float z, float r)
 
        o->sph.rad = r;
        mat4_translation(o->ob.xform, x, y, z);
-       mat4_copy(o->ob.inv_xform, o->ob.xform);
-       mat4_inverse(o->ob.inv_xform);
+       mat4_translation(o->ob.inv_xform, -x, -y, -z);
        return o;
 }
 
 csg_object *csg_cylinder(float x0, float y0, float z0, float x1, float y1, float z1, float r)
 {
        csg_object *o;
-       float dx, dy, dz;
+       float x, y, z, dx, dy, dz;
        int major;
 
        if(!(o = alloc_object(OB_CYLINDER))) {
                return 0;
        }
+       o->cyl.rad = r;
 
        dx = x1 - x0;
        dy = y1 - y0;
        dz = z1 - z0;
 
+       o->cyl.height = sqrt(dx * dx + dy * dy + dz * dz);
+
        if(fabs(dx) > fabs(dy) && fabs(dx) > fabs(dz)) {
                major = 0;
        } else if(fabs(dy) > fabs(dz)) {
@@ -209,8 +232,11 @@ csg_object *csg_cylinder(float x0, float y0, float z0, float x1, float y1, float
                major = 2;
        }
 
-       o->cyl.rad = r;
-       mat4_lookat(o->ob.xform, x0, y0, z0, x1, y1, z1, 0, major == 2 ? 1 : 0, major == 2 ? 0 : 1);
+       x = (x0 + x1) / 2.0f;
+       y = (y0 + y1) / 2.0f;
+       z = (z0 + z1) / 2.0f;
+
+       mat4_lookat(o->ob.xform, x, y, z, dx, dz, -dy, 0, major == 2 ? 0 : 1, major == 2 ? 1 : 0);
        mat4_copy(o->ob.inv_xform, o->ob.xform);
        mat4_inverse(o->ob.inv_xform);
        return o;
@@ -236,13 +262,28 @@ csg_object *csg_plane(float x, float y, float z, float nx, float ny, float nz)
        o->plane.nx = nx;
        o->plane.ny = ny;
        o->plane.nz = nz;
-       o->plane.d = x * nx + y * ny + z * nz;
+       o->plane.d = 0.0f;
+
+       mat4_translation(o->ob.xform, x, y, z);
+       mat4_translation(o->ob.inv_xform, -x, -y, -z);
        return o;
 }
 
 csg_object *csg_box(float x, float y, float z, float xsz, float ysz, float zsz)
 {
-       return 0;
+       csg_object *o;
+
+       if(!(o = alloc_object(OB_BOX))) {
+               return 0;
+       }
+
+       o->box.xsz = xsz;
+       o->box.ysz = ysz;
+       o->box.zsz = zsz;
+
+       mat4_translation(o->ob.xform, x, y, z);
+       mat4_translation(o->ob.inv_xform, -x, -y, -z);
+       return o;
 }
 
 csg_object *csg_union(csg_object *a, csg_object *b)
@@ -351,6 +392,8 @@ void csg_render_pixel(int x, int y, int width, int height, float aspect, float *
 {
        struct ray ray;
 
+       csg_dbg_pixel = (x == 400 && y == 186);
+
        calc_primary_ray(&ray, x, y, width, height, aspect);
        ray_trace(&ray, color);
 }
@@ -370,14 +413,15 @@ void csg_render_image(float *pixels, int width, int height)
 
 static void calc_primary_ray(struct ray *ray, int x, int y, int w, int h, float aspect)
 {
-       /* TODO */
        ray->dx = aspect * ((float)x / (float)w * 2.0f - 1.0f);
        ray->dy = 1.0f - (float)y / (float)h * 2.0f;
        ray->dz = -1.0f / tan(cam.fov * 0.5f);
 
-       ray->x = cam.x;
-       ray->y = cam.y;
-       ray->z = cam.z;
+       ray->x = 0;
+       ray->y = 0;
+       ray->z = 0;
+
+       xform_ray(ray, cam.xform);
 }
 
 static int ray_trace(struct ray *ray, float *col)
@@ -423,7 +467,7 @@ static void shade(float *col, struct ray *ray, struct hit *hit)
                sray.dy = ldir[1];
                sray.dz = ldir[2];
 
-               if(!find_intersection(&sray, &tmphit) || tmphit.t > 1.0f) {
+               if(!find_intersection(&sray, &tmphit) || tmphit.t < 0.000001 || tmphit.t > 1.0f) {
                        if((len = sqrt(ldir[0] * ldir[0] + ldir[1] * ldir[1] + ldir[2] * ldir[2])) != 0.0f) {
                                float s = 1.0f / len;
                                ldir[0] *= s;
@@ -540,6 +584,13 @@ static csg_object *load_object(struct ts_node *node)
                        goto err;
                }
 
+       } else if(strcmp(node->name, "cylinder") == 0) {
+               float rad = ts_get_attr_num(node, "radius", 1.0f);
+               float height = ts_get_attr_num(node, "height", 1.0f);
+               if(!(o = csg_cylinder(0, -height/2.0f, 0, 0, height/2.0f, 0, rad))) {
+                       goto err;
+               }
+
        } else if(strcmp(node->name, "plane") == 0) {
                static float def_norm[] = {0, 1, 0};
                float *norm = ts_get_attr_vec(node, "normal", def_norm);