clray: 353d80127627 rt.cl

clray

view rt.cl @ 29:353d80127627

doh ... it doesn't work

author	John Tsiombikas <nuclear@member.fsf.org>
date	Sat, 21 Aug 2010 20:51:57 +0100
parents	97cfd9675310
children	04803c702014

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

102 struct Ray ray = primrays[idx];

103 transform_ray(&ray, xform, invtrans);

104

105 float4 pixel = (float4)(0, 0, 0, 0);

106 float4 energy = (float4)(1.0, 1.0, 1.0, 0.0);

107 int iter = 0;

108

109 while(iter++ < rinf->max_iter && mean(energy) > MIN_ENERGY) {

110 struct SurfPoint sp;

111 if(find_intersection(ray, &scn, &sp)) {

112 pixel += shade(ray, &scn, &sp) * energy;

113

114 float4 refl_col = sp.mat.ks * sp.mat.kr;

115

116 ray.origin = sp.pos;

117 ray.dir = reflect(-ray.dir, sp.norm);

118

119 energy *= sp.mat.ks * sp.mat.kr;

120 } else {

121 iter = INT_MAX - 1; // to break out of the loop

122 }

123 }

124

125 fb[idx] = pixel;

126 }

127

128 float4 shade(struct Ray ray, struct Scene *scn, const struct SurfPoint *sp)

129 {

130 float4 norm = sp->norm;

131 bool entering = true;

132

133 if(dot(ray.dir, norm) >= 0.0) {

134 norm = -norm;

135 entering = false;

136 }

137

138 float4 dcol = scn->ambient * sp->mat.kd;

139 float4 scol = (float4)(0, 0, 0, 0);

140

141 for(int i=0; i<scn->num_lights; i++) {

142 float4 ldir = scn->lights[i].pos - sp->pos;

143

144 struct Ray shadowray;

145 shadowray.origin = sp->pos;

146 shadowray.dir = ldir;

147

148 if(!find_intersection(shadowray, scn, 0)) {

149 ldir = normalize(ldir);

150 float4 vdir = -normalize(ray.dir);

151 float4 vref = reflect(vdir, norm);

152

153 float diff = fmax(dot(ldir, norm), 0.0f);

154 dcol += sp->mat.kd * scn->lights[i].color * diff;

155

156 float spec = powr(fmax(dot(ldir, vref), 0.0f), sp->mat.spow);

157 scol += sp->mat.ks * scn->lights[i].color * spec;

158 }

159 }

160

161 return dcol + scol;

162 }

163

164 #define STACK_SIZE 128

165 bool find_intersection(struct Ray ray, const struct Scene *scn, struct SurfPoint *spres)

166 {

167 struct SurfPoint sp0;

168 sp0.t = 1.0;

169 sp0.obj = 0;

170

171 int idxstack[STACK_SIZE];

172 int sp = 0; // points at the topmost element of the stack

173 idxstack[sp] = 1; // root at tree[1] (heap)

174

175 while(sp >= 0) {

176 int idx = idxstack[sp--]; // remove this index from the stack and process it

177

178 global struct KDNode *node = scn->kdtree + idx;

179

180 if(intersect_aabb(ray, node->aabb)) {

181 // leaf node ...

182 if(node->num_faces) {

183 // check each face in turn and update the nearest intersection as needed

184 for(int i=0; i<node->num_faces; i++) {

185 struct SurfPoint sp;

186 int fidx = node->face_idx[i];

187

188 if(intersect(ray, scn->faces + fidx, &sp) && sp.t < sp0.t) {

189 sp0 = sp;

190 }

191 }

192 }

193 } else {

194 // internal node ... recurse to the children

195 idxstack[++sp] = idx * 2;

196 idxstack[++sp] = idx * 2 + 1;

197 }

198 }

199

200 if(!sp0.obj) {

201 return false;

202 }

203

204 if(spres) {

205 *spres = sp0;

206 spres->mat = scn->matlib[sp0.obj->matid];

207 }

208 return true;

209 }

210

211 /*bool find_intersection(struct Ray ray, const struct Scene *scn, struct SurfPoint *spres)

212 {

213 struct SurfPoint sp, sp0;

214 sp0.t = 1.0;

215 sp0.obj = 0;

216

217 for(int i=0; i<scn->num_faces; i++) {

218 if(intersect(ray, scn->faces + i, &sp) && sp.t < sp0.t) {

219 sp0 = sp;

220 }

221 }

222

223 if(!sp0.obj) {

224 return false;

225 }

226

227 if(spres) {

228 *spres = sp0;

229 spres->mat = scn->matlib[sp0.obj->matid];

230 }

231 return true;

232 }*/

233

234 bool intersect(struct Ray ray, global const struct Face *face, struct SurfPoint *sp)

235 {

236 float4 origin = ray.origin;

237 float4 dir = ray.dir;

238 float4 norm = face->normal;

239

240 float ndotdir = dot(dir, norm);

241

242 if(fabs(ndotdir) <= EPSILON) {

243 return false;

244 }

245

246 float4 pt = face->v[0].pos;

247 float4 vec = pt - origin;

248

249 float ndotvec = dot(norm, vec);

250 float t = ndotvec / ndotdir;

251

252 if(t < EPSILON || t > 1.0) {

253 return false;

254 }

255 pt = origin + dir * t;

256

257

258 float4 bc = calc_bary(pt, face, norm);

259 float bc_sum = bc.x + bc.y + bc.z;

260

261 if(bc_sum < 1.0 - EPSILON || bc_sum > 1.0 + EPSILON) {

262 return false;

263 bc *= 1.2;

264 }

265

266 sp->t = t;

267 sp->pos = pt;

268 sp->norm = normalize(face->v[0].normal * bc.x + face->v[1].normal * bc.y + face->v[2].normal * bc.z);

269 sp->obj = face;

270 sp->dbg = bc;

271 return true;

272 }

273

274 bool intersect_aabb(struct Ray ray, struct AABBox aabb)

275 {

276 if(ray.origin.x >= aabb.min.x && ray.origin.y >= aabb.min.y && ray.origin.z >= aabb.min.z &&

277 ray.origin.x < aabb.max.x && ray.origin.y < aabb.max.y && ray.origin.z < aabb.max.z) {

278 return true;

279 }

280

281 float4 bbox[2] = {

282 aabb.min.x, aabb.min.y, aabb.min.z, 0,

283 aabb.max.x, aabb.max.y, aabb.max.z, 0

284 };

285

286 int xsign = (int)(ray.dir.x < 0.0);

287 float invdirx = 1.0 / ray.dir.x;

288 float tmin = (bbox[xsign].x - ray.origin.x) * invdirx;

289 float tmax = (bbox[1 - xsign].x - ray.origin.x) * invdirx;

290

291 int ysign = (int)(ray.dir.y < 0.0);

292 float invdiry = 1.0 / ray.dir.y;

293 float tymin = (bbox[ysign].y - ray.origin.y) * invdiry;

294 float tymax = (bbox[1 - ysign].y - ray.origin.y) * invdiry;

295

296 if(tmin > tymax || tymin > tmax) {

297 return false;

298 }

299

300 if(tymin > tmin) tmin = tymin;

301 if(tymax < tmax) tmax = tymax;

302

303 int zsign = (int)(ray.dir.z < 0.0);

304 float invdirz = 1.0 / ray.dir.z;

305 float tzmin = (bbox[zsign].z - ray.origin.z) * invdirz;

306 float tzmax = (bbox[1 - zsign].z - ray.origin.z) * invdirz;

307

308 if(tmin > tzmax || tzmin > tmax) {

309 return false;

310 }

311

312 return tmin < 1.0 && tmax > 0.0;

313 }

314

315 float4 reflect(float4 v, float4 n)

316 {

317 return 2.0f * dot(v, n) * n - v;

318 }

319

320 float4 transform(float4 v, global const float *xform)

321 {

322 float4 res;

323 res.x = v.x * xform[0] + v.y * xform[4] + v.z * xform[8] + xform[12];

324 res.y = v.x * xform[1] + v.y * xform[5] + v.z * xform[9] + xform[13];

325 res.z = v.x * xform[2] + v.y * xform[6] + v.z * xform[10] + xform[14];

326 res.w = 0.0;

327 return res;

328 }

329

330 void transform_ray(struct Ray *ray, global const float *xform, global const float *invtrans)

331 {

332 ray->origin = transform(ray->origin, xform);

333 ray->dir = transform(ray->dir, invtrans);

334 }

335

336 float4 calc_bary(float4 pt, global const struct Face *face, float4 norm)

337 {

338 float4 bc = (float4)(0, 0, 0, 0);

339

340 // calculate area of the whole triangle

341 float4 v1 = face->v[1].pos - face->v[0].pos;

342 float4 v2 = face->v[2].pos - face->v[0].pos;

343 float4 xv1v2 = cross(v1, v2);

344

345 float area = fabs(dot(xv1v2, norm)) * 0.5;

346 if(area < EPSILON) {

347 return bc;

348 }

349

350 float4 pv0 = face->v[0].pos - pt;

351 float4 pv1 = face->v[1].pos - pt;

352 float4 pv2 = face->v[2].pos - pt;

353

354 // calculate the area of each sub-triangle

355 float4 x12 = cross(pv1, pv2);

356 float4 x20 = cross(pv2, pv0);

357 float4 x01 = cross(pv0, pv1);

358

359 float a0 = fabs(dot(x12, norm)) * 0.5;

360 float a1 = fabs(dot(x20, norm)) * 0.5;

361 float a2 = fabs(dot(x01, norm)) * 0.5;

362

363 bc.x = a0 / area;

364 bc.y = a1 / area;

365 bc.z = a2 / area;

366 return bc;

367 }

368

369 float mean(float4 v)

370 {

371 return native_divide(v.x + v.y + v.z, 3.0);

372 }