clray
view rt.cl @ 30:04803c702014
debugging ...
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Sat, 21 Aug 2010 23:57:19 +0100 |
| parents | 353d80127627 |
| children | 92786fc3317e |
line source
1 /* vim: set ft=opencl:ts=4:sw=4 */
3 struct RendInfo {
4 float4 ambient;
5 int xsz, ysz;
6 int num_faces, num_lights;
7 int max_iter;
8 int kd_depth;
9 };
11 struct Vertex {
12 float4 pos;
13 float4 normal;
14 float4 tex;
15 float4 padding;
16 };
18 struct Face {
19 struct Vertex v[3];
20 float4 normal;
21 int matid;
22 int padding[3];
23 };
25 struct Material {
26 float4 kd, ks;
27 float kr, kt;
28 float spow;
29 float padding;
30 };
32 struct Light {
33 float4 pos, color;
34 };
36 struct Ray {
37 float4 origin, dir;
38 };
40 struct SurfPoint {
41 float t;
42 float4 pos, norm, dbg;
43 global const struct Face *obj;
44 struct Material mat;
45 };
47 struct Scene {
48 float4 ambient;
49 global const struct Face *faces;
50 int num_faces;
51 global const struct Light *lights;
52 int num_lights;
53 global const struct Material *matlib;
54 global const struct KDNode *kdtree;
55 };
57 struct AABBox {
58 float4 min, max;
59 };
61 struct KDNode {
62 struct AABBox aabb;
63 int face_idx[32];
64 int num_faces;
65 int padding[3];
66 };
68 #define MIN_ENERGY 0.001
69 #define EPSILON 1e-5
71 float4 shade(struct Ray ray, struct Scene *scn, const struct SurfPoint *sp);
72 bool find_intersection(struct Ray ray, const struct Scene *scn, struct SurfPoint *sp);
73 bool intersect(struct Ray ray, global const struct Face *face, struct SurfPoint *sp);
74 bool intersect_aabb(struct Ray ray, struct AABBox aabb);
76 float4 reflect(float4 v, float4 n);
77 float4 transform(float4 v, global const float *xform);
78 void transform_ray(struct Ray *ray, global const float *xform, global const float *invtrans);
79 float4 calc_bary(float4 pt, global const struct Face *face, float4 norm);
80 float mean(float4 v);
82 kernel void render(global float4 *fb,
83 global const struct RendInfo *rinf,
84 global const struct Face *faces,
85 global const struct Material *matlib,
86 global const struct Light *lights,
87 global const struct Ray *primrays,
88 global const float *xform,
89 global const float *invtrans,
90 global const struct KDNode *kdtree)
91 {
92 int idx = get_global_id(0);
94 struct Scene scn;
95 scn.ambient = rinf->ambient;
96 scn.faces = faces;
97 scn.num_faces = rinf->num_faces;
98 scn.lights = lights;
99 scn.num_lights = rinf->num_lights;
100 scn.matlib = matlib;
101 scn.kdtree = kdtree;
103 struct Ray ray = primrays[idx];
104 transform_ray(&ray, xform, invtrans);
106 float4 pixel = (float4)(0, 0, 0, 0);
107 float4 energy = (float4)(1.0, 1.0, 1.0, 0.0);
108 int iter = 0;
110 while(iter++ < rinf->max_iter && mean(energy) > MIN_ENERGY) {
111 struct SurfPoint sp;
112 if(find_intersection(ray, &scn, &sp)) {
113 pixel += shade(ray, &scn, &sp) * energy;
115 float4 refl_col = sp.mat.ks * sp.mat.kr;
117 ray.origin = sp.pos;
118 ray.dir = reflect(-ray.dir, sp.norm);
120 energy *= sp.mat.ks * sp.mat.kr;
121 } else {
122 iter = INT_MAX - 1; // to break out of the loop
123 }
124 }
126 fb[idx] = pixel;
127 }
129 float4 shade(struct Ray ray, struct Scene *scn, const struct SurfPoint *sp)
130 {
131 float4 norm = sp->norm;
132 bool entering = true;
134 if(dot(ray.dir, norm) >= 0.0) {
135 norm = -norm;
136 entering = false;
137 }
139 float4 dcol = scn->ambient * sp->mat.kd;
140 float4 scol = (float4)(0, 0, 0, 0);
142 for(int i=0; i<scn->num_lights; i++) {
143 float4 ldir = scn->lights[i].pos - sp->pos;
145 struct Ray shadowray;
146 shadowray.origin = sp->pos;
147 shadowray.dir = ldir;
149 if(!find_intersection(shadowray, scn, 0)) {
150 ldir = normalize(ldir);
151 float4 vdir = -normalize(ray.dir);
152 float4 vref = reflect(vdir, norm);
154 float diff = fmax(dot(ldir, norm), 0.0f);
155 dcol += sp->mat.kd * scn->lights[i].color * diff;
157 float spec = powr(fmax(dot(ldir, vref), 0.0f), sp->mat.spow);
158 scol += sp->mat.ks * scn->lights[i].color * spec;
159 }
160 }
162 return dcol + scol;
163 }
165 #define STACK_SIZE 64
166 bool find_intersection(struct Ray ray, const struct Scene *scn, struct SurfPoint *spres)
167 {
168 struct SurfPoint sp0;
169 sp0.t = 1.0;
170 sp0.obj = 0;
172 int idxstack[STACK_SIZE];
173 int sp = 0; // points at the topmost element of the stack
174 idxstack[sp] = 1; // root at tree[1] (heap)
176 printf("check intersection\n");
178 while(sp >= 0) {
179 int idx = idxstack[sp--]; // remove this index from the stack and process it
181 global struct KDNode *node = scn->kdtree + idx;
182 printf("idx: %d (%p) num_faces: %d\n", idx, node, node->num_faces);
184 if(intersect_aabb(ray, node->aabb)) {
185 // leaf node ...
186 if(node->num_faces >= 0) {
187 // check each face in turn and update the nearest intersection as needed
188 for(int i=0; i<node->num_faces; i++) {
189 struct SurfPoint sp;
190 int fidx = node->face_idx[i];
192 if(intersect(ray, scn->faces + fidx, &sp) && sp.t < sp0.t) {
193 sp0 = sp;
194 }
195 }
196 }
197 } else {
198 // internal node ... recurse to the children
199 idxstack[++sp] = idx * 2;
200 idxstack[++sp] = idx * 2 + 1;
201 }
202 }
204 if(!sp0.obj) {
205 return false;
206 }
208 if(spres) {
209 *spres = sp0;
210 spres->mat = scn->matlib[sp0.obj->matid];
211 }
212 return true;
213 }
215 /*bool find_intersection(struct Ray ray, const struct Scene *scn, struct SurfPoint *spres)
216 {
217 struct SurfPoint sp, sp0;
218 sp0.t = 1.0;
219 sp0.obj = 0;
221 for(int i=0; i<scn->num_faces; i++) {
222 if(intersect(ray, scn->faces + i, &sp) && sp.t < sp0.t) {
223 sp0 = sp;
224 }
225 }
227 if(!sp0.obj) {
228 return false;
229 }
231 if(spres) {
232 *spres = sp0;
233 spres->mat = scn->matlib[sp0.obj->matid];
234 }
235 return true;
236 }*/
238 bool intersect(struct Ray ray, global const struct Face *face, struct SurfPoint *sp)
239 {
240 float4 origin = ray.origin;
241 float4 dir = ray.dir;
242 float4 norm = face->normal;
244 float ndotdir = dot(dir, norm);
246 if(fabs(ndotdir) <= EPSILON) {
247 return false;
248 }
250 float4 pt = face->v[0].pos;
251 float4 vec = pt - origin;
253 float ndotvec = dot(norm, vec);
254 float t = ndotvec / ndotdir;
256 if(t < EPSILON || t > 1.0) {
257 return false;
258 }
259 pt = origin + dir * t;
262 float4 bc = calc_bary(pt, face, norm);
263 float bc_sum = bc.x + bc.y + bc.z;
265 if(bc_sum < 1.0 - EPSILON || bc_sum > 1.0 + EPSILON) {
266 return false;
267 bc *= 1.2;
268 }
270 sp->t = t;
271 sp->pos = pt;
272 sp->norm = normalize(face->v[0].normal * bc.x + face->v[1].normal * bc.y + face->v[2].normal * bc.z);
273 sp->obj = face;
274 sp->dbg = bc;
275 return true;
276 }
278 bool intersect_aabb(struct Ray ray, struct AABBox aabb)
279 {
280 if(ray.origin.x >= aabb.min.x && ray.origin.y >= aabb.min.y && ray.origin.z >= aabb.min.z &&
281 ray.origin.x < aabb.max.x && ray.origin.y < aabb.max.y && ray.origin.z < aabb.max.z) {
282 return true;
283 }
285 float4 bbox[2] = {
286 aabb.min.x, aabb.min.y, aabb.min.z, 0,
287 aabb.max.x, aabb.max.y, aabb.max.z, 0
288 };
290 int xsign = (int)(ray.dir.x < 0.0);
291 float invdirx = 1.0 / ray.dir.x;
292 float tmin = (bbox[xsign].x - ray.origin.x) * invdirx;
293 float tmax = (bbox[1 - xsign].x - ray.origin.x) * invdirx;
295 int ysign = (int)(ray.dir.y < 0.0);
296 float invdiry = 1.0 / ray.dir.y;
297 float tymin = (bbox[ysign].y - ray.origin.y) * invdiry;
298 float tymax = (bbox[1 - ysign].y - ray.origin.y) * invdiry;
300 if(tmin > tymax || tymin > tmax) {
301 return false;
302 }
304 if(tymin > tmin) tmin = tymin;
305 if(tymax < tmax) tmax = tymax;
307 int zsign = (int)(ray.dir.z < 0.0);
308 float invdirz = 1.0 / ray.dir.z;
309 float tzmin = (bbox[zsign].z - ray.origin.z) * invdirz;
310 float tzmax = (bbox[1 - zsign].z - ray.origin.z) * invdirz;
312 if(tmin > tzmax || tzmin > tmax) {
313 return false;
314 }
316 return tmin < 1.0 && tmax > 0.0;
317 }
319 float4 reflect(float4 v, float4 n)
320 {
321 return 2.0f * dot(v, n) * n - v;
322 }
324 float4 transform(float4 v, global const float *xform)
325 {
326 float4 res;
327 res.x = v.x * xform[0] + v.y * xform[4] + v.z * xform[8] + xform[12];
328 res.y = v.x * xform[1] + v.y * xform[5] + v.z * xform[9] + xform[13];
329 res.z = v.x * xform[2] + v.y * xform[6] + v.z * xform[10] + xform[14];
330 res.w = 0.0;
331 return res;
332 }
334 void transform_ray(struct Ray *ray, global const float *xform, global const float *invtrans)
335 {
336 ray->origin = transform(ray->origin, xform);
337 ray->dir = transform(ray->dir, invtrans);
338 }
340 float4 calc_bary(float4 pt, global const struct Face *face, float4 norm)
341 {
342 float4 bc = (float4)(0, 0, 0, 0);
344 // calculate area of the whole triangle
345 float4 v1 = face->v[1].pos - face->v[0].pos;
346 float4 v2 = face->v[2].pos - face->v[0].pos;
347 float4 xv1v2 = cross(v1, v2);
349 float area = fabs(dot(xv1v2, norm)) * 0.5;
350 if(area < EPSILON) {
351 return bc;
352 }
354 float4 pv0 = face->v[0].pos - pt;
355 float4 pv1 = face->v[1].pos - pt;
356 float4 pv2 = face->v[2].pos - pt;
358 // calculate the area of each sub-triangle
359 float4 x12 = cross(pv1, pv2);
360 float4 x20 = cross(pv2, pv0);
361 float4 x01 = cross(pv0, pv1);
363 float a0 = fabs(dot(x12, norm)) * 0.5;
364 float a1 = fabs(dot(x20, norm)) * 0.5;
365 float a2 = fabs(dot(x01, norm)) * 0.5;
367 bc.x = a0 / area;
368 bc.y = a1 / area;
369 bc.z = a2 / area;
370 return bc;
371 }
373 float mean(float4 v)
374 {
375 return native_divide(v.x + v.y + v.z, 3.0);
376 }