#include <stdlib.h>
#include <string.h>
#include <math.h>
-#include "csgray.h"
+#include <float.h>
+#include "csgimpl.h"
#include "matrix.h"
+#include "geom.h"
-enum {
- OB_NULL,
- OB_SPHERE,
- OB_CYLINDER,
- OB_PLANE,
- OB_BOX,
- OB_UNION,
- OB_INTERSECTION,
- OB_SUBTRACTION
-};
-
-struct object {
- int type;
-
- float r, g, b;
- float emr, emg, emb;
- float roughness;
- float opacity;
-
- float xform[16];
-
- struct object *next;
- struct object *clist, *ctail;
- struct object *parent;
-};
-
-struct sphere {
- struct object ob;
- float rad;
-};
-
-struct plane {
- struct object ob;
- float nx, ny, nz;
- float d;
-};
-
-union csg_object {
- struct object ob;
- struct sphere sph;
- struct plane plane;
-};
-
-struct camera {
- float x, y, z;
- float tx, ty, tz;
- float fov;
-};
+static void calc_primary_ray(struct ray *ray, int x, int y, int w, int h, float aspect);
+static int ray_trace(struct ray *ray, float *col);
+static void shade(float *col, struct ray *ray, struct hit *hit);
+static void background(float *col, struct ray *ray);
+static int find_intersection(struct ray *ray, struct hit *best);
+static float ambient[3];
static struct camera cam;
-static csg_object *root;
+static csg_object *oblist;
+static csg_object *plights;
int csg_init(void)
{
- if(!(root = csg_null(0, 0, 0))) {
- return -1;
- }
+ oblist = 0;
+ plights = 0;
+ csg_ambient(0.05, 0.05, 0.05);
csg_view(0, 0, 5, 0, 0, 0);
csg_fov(50);
void csg_destroy(void)
{
- csg_free_object(root);
- root = 0;
+ while(oblist) {
+ csg_object *o = oblist;
+ oblist = oblist->ob.next;
+ csg_free_object(o);
+ }
+ oblist = 0;
}
void csg_view(float x, float y, float z, float tx, float ty, float tz)
return 0; /* TODO */
}
-#define OBPTR(o) ((struct object*)(o))
-
-void csg_add_object(csg_object *parent, csg_object *child)
+void csg_add_object(csg_object *o)
{
- if(!parent) {
- parent = root;
- }
+ o->ob.next = oblist;
+ oblist = o;
- if(parent->ob.clist) {
- parent->ob.ctail->next = OBPTR(child);
- parent->ob.ctail = OBPTR(child);
- } else {
- parent->ob.clist = parent->ob.ctail = OBPTR(child);
+ if(o->ob.type == OB_NULL && (o->ob.emr > 0.0f || o->ob.emg > 0.0f || o->ob.emb > 0.0f)) {
+ o->ob.plt_next = plights;
+ plights = o;
}
- child->ob.parent = OBPTR(parent);
}
-void csg_remove_object(csg_object *parent, csg_object *child)
+int csg_remove_object(csg_object *o)
{
- csg_object *c;
+ csg_object dummy, *n;
- if(!parent) {
- parent = root;
- }
+ dummy.ob.next = oblist;
+ n = &dummy;
- c = (csg_object*)parent->ob.clist;
- while(c->ob.next) {
- if(c->ob.next == OBPTR(child)) {
- c->ob.next = child->ob.next;
- child->ob.next = 0;
- child->ob.parent = 0;
- return;
+ while(n->ob.next) {
+ if(n->ob.next == o) {
+ n->ob.next = o->ob.next;
+ return 1;
}
- c = (csg_object*)c->ob.next;
+ n = n->ob.next;
}
+ return 0;
}
void csg_free_object(csg_object *o)
{
- csg_object *c = (csg_object*)o->ob.clist;
- while(c) {
- csg_object *tmp = c;
- c = (csg_object*)c->ob.next;
- csg_free_object(tmp);
+ if(o->ob.destroy) {
+ o->ob.destroy(o);
}
free(o);
}
-static union csg_object *alloc_object(void)
+static union csg_object *alloc_object(int type)
{
csg_object *o;
if(!(o = calloc(sizeof *o, 1))) {
return 0;
}
- o->ob.type = OB_NULL;
+ o->ob.type = type;
mat4_identity(o->ob.xform);
+ mat4_identity(o->ob.inv_xform);
csg_emission(o, 0, 0, 0);
csg_color(o, 1, 1, 1);
csg_object *csg_null(float x, float y, float z)
{
- return alloc_object();
+ csg_object *o;
+
+ if(!(o = alloc_object(OB_NULL))) {
+ return 0;
+ }
+
+ mat4_translation(o->ob.xform, x, y, z);
+ return o;
}
csg_object *csg_sphere(float x, float y, float z, float r)
{
csg_object *o;
- if(!(o = alloc_object())) {
+ if(!(o = alloc_object(OB_SPHERE))) {
return 0;
}
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);
return o;
}
csg_object *csg_cylinder(float x0, float y0, float z0, float x1, float y1, float z1, float r)
{
- return 0;
+ csg_object *o;
+ float dx, dy, dz;
+ int major;
+
+ if(!(o = alloc_object(OB_CYLINDER))) {
+ return 0;
+ }
+
+ dx = x1 - x0;
+ dy = y1 - y0;
+ dz = z1 - z0;
+
+ if(fabs(dx) > fabs(dy) && fabs(dx) > fabs(dz)) {
+ major = 0;
+ } else if(fabs(dy) > fabs(dz)) {
+ major = 1;
+ } else {
+ 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);
+ mat4_copy(o->ob.inv_xform, o->ob.xform);
+ mat4_inverse(o->ob.inv_xform);
+ return o;
}
csg_object *csg_plane(float x, float y, float z, float nx, float ny, float nz)
{
+ csg_object *o;
+ float len;
+
+ if(!(o = alloc_object(OB_PLANE))) {
+ return 0;
+ }
+
+ len = sqrt(nx * nx + ny * ny + nz * nz);
+ if(len != 0.0f) {
+ float s = 1.0f / len;
+ nx *= s;
+ ny *= s;
+ nz *= s;
+ }
+
+ o->plane.nx = nx;
+ o->plane.ny = ny;
+ o->plane.nz = nz;
+ o->plane.d = x * nx + y * ny + z * nz;
return 0;
}
return 0;
}
-
csg_object *csg_union(csg_object *a, csg_object *b)
{
- return 0;
+ csg_object *o;
+
+ if(!(o = alloc_object(OB_UNION))) {
+ return 0;
+ }
+ o->un.a = a;
+ o->un.b = b;
+ return o;
}
csg_object *csg_intersection(csg_object *a, csg_object *b)
{
- return 0;
+ csg_object *o;
+
+ if(!(o = alloc_object(OB_INTERSECTION))) {
+ return 0;
+ }
+ o->isect.a = a;
+ o->isect.b = b;
+ return o;
}
csg_object *csg_subtraction(csg_object *a, csg_object *b)
{
- return 0;
+ csg_object *o;
+
+ if(!(o = alloc_object(OB_SUBTRACTION))) {
+ return 0;
+ }
+ o->sub.a = a;
+ o->sub.b = b;
+ return o;
}
+void csg_ambient(float r, float g, float b)
+{
+ ambient[0] = r;
+ ambient[1] = g;
+ ambient[2] = b;
+}
void csg_emission(csg_object *o, float r, float g, float b)
{
+ o->ob.emr = r;
+ o->ob.emg = g;
+ o->ob.emb = b;
}
void csg_color(csg_object *o, float r, float g, float b)
{
+ o->ob.r = r;
+ o->ob.g = g;
+ o->ob.b = b;
}
void csg_roughness(csg_object *o, float r)
{
+ o->ob.roughness = r;
}
void csg_opacity(csg_object *o, float p)
{
+ o->ob.opacity = p;
}
-void csg_render_pixel(int x, int y, float *color)
+void csg_render_pixel(int x, int y, int width, int height, float aspect, float *color)
{
+ struct ray ray;
+
+ calc_primary_ray(&ray, x, y, width, height, aspect);
+ ray_trace(&ray, color);
}
void csg_render_image(float *pixels, int width, int height)
{
+ int i, j;
+ float aspect = (float)width / (float)height;
+
+ for(i=0; i<height; i++) {
+ for(j=0; j<width; j++) {
+ csg_render_pixel(j, i, width, height, aspect, pixels);
+ pixels += 3;
+ }
+ }
+}
+
+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;
+}
+
+static int ray_trace(struct ray *ray, float *col)
+{
+ struct hit hit;
+
+ if(!find_intersection(ray, &hit)) {
+ background(col, ray);
+ return 0;
+ }
+
+ shade(col, ray, &hit);
+ return 1;
+}
+
+#define NULLXPOS(o) ((o)->ob.xform[12])
+#define NULLYPOS(o) ((o)->ob.xform[13])
+#define NULLZPOS(o) ((o)->ob.xform[14])
+
+static void shade(float *col, struct ray *ray, struct hit *hit)
+{
+ float ndotl, len;
+ csg_object *o, *lt = plights;
+ float dcol[3], scol[3] = {0};
+ float ldir[3];
+ struct ray sray;
+ struct hit tmphit;
+
+ o = hit->o;
+ dcol[0] = ambient[0];
+ dcol[1] = ambient[1];
+ dcol[2] = ambient[2];
+
+ while(lt) {
+ ldir[0] = NULLXPOS(lt) - hit->x;
+ ldir[1] = NULLYPOS(lt) - hit->y;
+ ldir[2] = NULLZPOS(lt) - hit->z;
+
+ sray.x = hit->x;
+ sray.y = hit->y;
+ sray.z = hit->z;
+ sray.dx = ldir[0];
+ sray.dy = ldir[1];
+ sray.dz = ldir[2];
+
+ if(!find_intersection(&sray, &tmphit) || 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;
+ ldir[1] *= s;
+ ldir[2] *= s;
+ }
+
+ if((ndotl = hit->nx * ldir[0] + hit->ny * ldir[1] + hit->nz * ldir[2]) < 0.0f) {
+ ndotl = 0.0f;
+ }
+
+ dcol[0] += o->ob.r * lt->ob.emr * ndotl;
+ dcol[1] += o->ob.g * lt->ob.emg * ndotl;
+ dcol[2] += o->ob.b * lt->ob.emb * ndotl;
+ }
+
+ lt = lt->ob.next;
+ }
+
+ col[0] = dcol[0] + scol[0];
+ col[1] = dcol[1] + scol[1];
+ col[2] = dcol[2] + scol[2];
+}
+
+static void background(float *col, struct ray *ray)
+{
+ col[0] = col[1] = col[2] = 0.0f;
+}
+
+static int find_intersection(struct ray *ray, struct hit *best)
+{
+ csg_object *o;
+ struct hit *hit;
+
+ best->t = FLT_MAX;
+ best->o = 0;
+
+ o = oblist;
+ while(o) {
+ if((hit = ray_intersect(ray, o)) && hit->t < best->t) {
+ *best = *hit;
+ }
+ free_hit_list(hit);
+ o = o->ob.next;
+ }
+
+ return best->o != 0;
}