rev |
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nuclear@12
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1 /* vim: set ft=opencl:ts=4:sw=4 */
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nuclear@12
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2
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nuclear@2
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3 struct RendInfo {
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nuclear@22
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4 float4 ambient;
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nuclear@2
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5 int xsz, ysz;
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nuclear@9
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6 int num_faces, num_lights;
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nuclear@2
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7 int max_iter;
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nuclear@28
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8 int kd_depth;
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nuclear@2
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9 };
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nuclear@2
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10
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nuclear@9
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11 struct Vertex {
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nuclear@2
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12 float4 pos;
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nuclear@9
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13 float4 normal;
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nuclear@12
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14 float4 tex;
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nuclear@12
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15 float4 padding;
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nuclear@9
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16 };
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nuclear@9
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17
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nuclear@9
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18 struct Face {
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nuclear@9
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19 struct Vertex v[3];
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nuclear@9
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20 float4 normal;
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nuclear@9
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21 int matid;
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nuclear@12
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22 int padding[3];
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nuclear@9
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23 };
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nuclear@9
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24
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nuclear@9
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25 struct Material {
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nuclear@5
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26 float4 kd, ks;
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nuclear@9
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27 float kr, kt;
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nuclear@9
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28 float spow;
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nuclear@12
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29 float padding;
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nuclear@2
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30 };
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nuclear@2
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31
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nuclear@3
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32 struct Light {
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nuclear@3
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33 float4 pos, color;
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nuclear@3
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34 };
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nuclear@3
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35
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nuclear@2
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36 struct Ray {
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nuclear@2
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37 float4 origin, dir;
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nuclear@2
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38 };
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nuclear@2
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39
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nuclear@2
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40 struct SurfPoint {
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nuclear@2
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41 float t;
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nuclear@12
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42 float4 pos, norm, dbg;
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nuclear@9
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43 global const struct Face *obj;
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nuclear@19
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44 struct Material mat;
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nuclear@2
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45 };
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nuclear@2
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46
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nuclear@16
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47 struct Scene {
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nuclear@16
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48 float4 ambient;
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nuclear@16
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49 global const struct Face *faces;
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nuclear@16
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50 int num_faces;
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nuclear@16
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51 global const struct Light *lights;
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nuclear@16
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52 int num_lights;
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nuclear@16
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53 global const struct Material *matlib;
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nuclear@28
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54 global const struct KDNode *kdtree;
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nuclear@28
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55 };
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nuclear@28
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56
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nuclear@28
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57 struct AABBox {
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nuclear@28
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58 float4 min, max;
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nuclear@28
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59 };
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nuclear@28
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60
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nuclear@28
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61 struct KDNode {
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nuclear@29
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62 struct AABBox aabb;
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nuclear@28
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63 int face_idx[32];
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nuclear@28
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64 int num_faces;
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nuclear@35
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65 int left, right;
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nuclear@35
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66 int padding;
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nuclear@16
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67 };
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nuclear@2
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68
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nuclear@16
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69 #define MIN_ENERGY 0.001
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nuclear@21
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70 #define EPSILON 1e-5
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nuclear@16
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71
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nuclear@16
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72 float4 shade(struct Ray ray, struct Scene *scn, const struct SurfPoint *sp);
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nuclear@16
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73 bool find_intersection(struct Ray ray, const struct Scene *scn, struct SurfPoint *sp);
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nuclear@9
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74 bool intersect(struct Ray ray, global const struct Face *face, struct SurfPoint *sp);
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nuclear@28
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75 bool intersect_aabb(struct Ray ray, struct AABBox aabb);
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nuclear@16
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76
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nuclear@8
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77 float4 reflect(float4 v, float4 n);
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nuclear@8
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78 float4 transform(float4 v, global const float *xform);
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nuclear@16
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79 void transform_ray(struct Ray *ray, global const float *xform, global const float *invtrans);
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nuclear@12
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80 float4 calc_bary(float4 pt, global const struct Face *face, float4 norm);
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nuclear@19
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81 float mean(float4 v);
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nuclear@4
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82
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nuclear@39
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83
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nuclear@39
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84 kernel void render(write_only image2d_t fb,
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nuclear@4
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85 global const struct RendInfo *rinf,
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nuclear@9
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86 global const struct Face *faces,
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nuclear@9
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87 global const struct Material *matlib,
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nuclear@4
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88 global const struct Light *lights,
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nuclear@7
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89 global const struct Ray *primrays,
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nuclear@12
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90 global const float *xform,
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nuclear@28
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91 global const float *invtrans,
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nuclear@28
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92 global const struct KDNode *kdtree)
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nuclear@2
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93 {
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nuclear@2
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94 int idx = get_global_id(0);
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nuclear@2
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95
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nuclear@16
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96 struct Scene scn;
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nuclear@16
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97 scn.ambient = rinf->ambient;
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nuclear@16
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98 scn.faces = faces;
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nuclear@16
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99 scn.num_faces = rinf->num_faces;
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nuclear@16
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100 scn.lights = lights;
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nuclear@16
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101 scn.num_lights = rinf->num_lights;
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nuclear@16
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102 scn.matlib = matlib;
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nuclear@30
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103 scn.kdtree = kdtree;
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nuclear@8
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104
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nuclear@16
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105 struct Ray ray = primrays[idx];
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nuclear@16
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106 transform_ray(&ray, xform, invtrans);
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nuclear@4
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107
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nuclear@19
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108 float4 pixel = (float4)(0, 0, 0, 0);
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nuclear@22
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109 float4 energy = (float4)(1.0, 1.0, 1.0, 0.0);
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nuclear@19
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110 int iter = 0;
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nuclear@19
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111
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nuclear@19
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112 while(iter++ < rinf->max_iter && mean(energy) > MIN_ENERGY) {
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nuclear@19
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113 struct SurfPoint sp;
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nuclear@19
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114 if(find_intersection(ray, &scn, &sp)) {
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nuclear@19
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115 pixel += shade(ray, &scn, &sp) * energy;
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nuclear@19
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116
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nuclear@19
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117 float4 refl_col = sp.mat.ks * sp.mat.kr;
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nuclear@19
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118
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nuclear@19
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119 ray.origin = sp.pos;
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nuclear@19
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120 ray.dir = reflect(-ray.dir, sp.norm);
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nuclear@19
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121
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nuclear@35
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122 energy *= refl_col;
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nuclear@19
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123 } else {
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nuclear@35
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124 break;
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nuclear@19
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125 }
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nuclear@17
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126 }
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nuclear@19
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127
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nuclear@39
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128 int img_x = get_image_width(fb);
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nuclear@39
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129
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nuclear@39
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130 int2 coord;
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nuclear@39
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131 coord.x = idx % img_x;
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nuclear@39
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132 coord.y = idx / img_x;
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nuclear@39
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133
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nuclear@39
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134 write_imagef(fb, coord, pixel);
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nuclear@4
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135 }
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nuclear@4
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136
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nuclear@16
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137 float4 shade(struct Ray ray, struct Scene *scn, const struct SurfPoint *sp)
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nuclear@16
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138 {
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nuclear@16
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139 float4 norm = sp->norm;
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nuclear@12
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140 bool entering = true;
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nuclear@12
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141
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nuclear@12
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142 if(dot(ray.dir, norm) >= 0.0) {
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nuclear@12
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143 norm = -norm;
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nuclear@12
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144 entering = false;
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nuclear@12
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145 }
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nuclear@12
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146
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nuclear@19
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147 float4 dcol = scn->ambient * sp->mat.kd;
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nuclear@8
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148 float4 scol = (float4)(0, 0, 0, 0);
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nuclear@5
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149
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nuclear@16
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150 for(int i=0; i<scn->num_lights; i++) {
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nuclear@16
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151 float4 ldir = scn->lights[i].pos - sp->pos;
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nuclear@5
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152
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nuclear@16
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153 struct Ray shadowray;
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nuclear@16
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154 shadowray.origin = sp->pos;
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nuclear@16
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155 shadowray.dir = ldir;
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nuclear@5
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156
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nuclear@16
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157 if(!find_intersection(shadowray, scn, 0)) {
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nuclear@16
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158 ldir = normalize(ldir);
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nuclear@16
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159 float4 vdir = -normalize(ray.dir);
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nuclear@16
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160 float4 vref = reflect(vdir, norm);
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nuclear@16
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161
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nuclear@16
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162 float diff = fmax(dot(ldir, norm), 0.0f);
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nuclear@22
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163 dcol += sp->mat.kd * scn->lights[i].color * diff;
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nuclear@16
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164
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nuclear@20
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165 float spec = powr(fmax(dot(ldir, vref), 0.0f), sp->mat.spow);
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nuclear@22
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166 scol += sp->mat.ks * scn->lights[i].color * spec;
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nuclear@16
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167 }
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nuclear@16
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168 }
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nuclear@16
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169
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nuclear@8
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170 return dcol + scol;
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nuclear@2
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171 }
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nuclear@2
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172
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nuclear@30
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173 #define STACK_SIZE 64
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nuclear@28
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174 bool find_intersection(struct Ray ray, const struct Scene *scn, struct SurfPoint *spres)
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nuclear@28
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175 {
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nuclear@29
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176 struct SurfPoint sp0;
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nuclear@29
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177 sp0.t = 1.0;
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nuclear@29
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178 sp0.obj = 0;
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nuclear@29
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179
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nuclear@29
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180 int idxstack[STACK_SIZE];
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nuclear@31
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181 int top = 0; // points after the topmost element of the stack
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nuclear@35
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182 idxstack[top++] = 0; // root at tree[0]
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nuclear@29
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183
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nuclear@31
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184 while(top > 0) {
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nuclear@31
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185 int idx = idxstack[--top]; // remove this index from the stack and process it
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nuclear@30
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186
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nuclear@31
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187 global const struct KDNode *node = scn->kdtree + idx;
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nuclear@29
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188
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nuclear@29
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189 if(intersect_aabb(ray, node->aabb)) {
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nuclear@35
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190 if(node->left == -1) {
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nuclear@31
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191 // leaf node... check each face in turn and update the nearest intersection as needed
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nuclear@29
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192 for(int i=0; i<node->num_faces; i++) {
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nuclear@31
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193 struct SurfPoint spt;
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nuclear@29
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194 int fidx = node->face_idx[i];
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nuclear@29
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195
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nuclear@31
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196 if(intersect(ray, scn->faces + fidx, &spt) && spt.t < sp0.t) {
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nuclear@31
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197 sp0 = spt;
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nuclear@29
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198 }
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nuclear@29
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199 }
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nuclear@31
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200 } else {
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nuclear@31
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201 // internal node... recurse to the children
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nuclear@35
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202 idxstack[top++] = node->left;
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nuclear@35
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203 idxstack[top++] = node->right;
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nuclear@29
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204 }
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nuclear@29
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205 }
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nuclear@29
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206 }
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nuclear@29
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207
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nuclear@29
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208 if(!sp0.obj) {
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nuclear@29
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209 return false;
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nuclear@29
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210 }
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nuclear@29
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211
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nuclear@29
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212 if(spres) {
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nuclear@29
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213 *spres = sp0;
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nuclear@29
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214 spres->mat = scn->matlib[sp0.obj->matid];
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nuclear@29
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215 }
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nuclear@29
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216 return true;
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nuclear@28
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217 }
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nuclear@16
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218
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nuclear@16
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219 bool intersect(struct Ray ray, global const struct Face *face, struct SurfPoint *sp)
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nuclear@2
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220 {
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nuclear@12
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221 float4 origin = ray.origin;
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nuclear@12
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222 float4 dir = ray.dir;
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nuclear@12
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223 float4 norm = face->normal;
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nuclear@12
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224
|
nuclear@16
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225 float ndotdir = dot(dir, norm);
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nuclear@12
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226
|
nuclear@9
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227 if(fabs(ndotdir) <= EPSILON) {
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nuclear@9
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228 return false;
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nuclear@9
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229 }
|
nuclear@2
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230
|
nuclear@9
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231 float4 pt = face->v[0].pos;
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nuclear@12
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232 float4 vec = pt - origin;
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nuclear@2
|
233
|
nuclear@16
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234 float ndotvec = dot(norm, vec);
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nuclear@9
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235 float t = ndotvec / ndotdir;
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nuclear@2
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236
|
nuclear@2
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237 if(t < EPSILON || t > 1.0) {
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nuclear@2
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238 return false;
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nuclear@2
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239 }
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nuclear@12
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240 pt = origin + dir * t;
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nuclear@9
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241
|
nuclear@12
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242
|
nuclear@12
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243 float4 bc = calc_bary(pt, face, norm);
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nuclear@9
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244 float bc_sum = bc.x + bc.y + bc.z;
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nuclear@9
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245
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nuclear@20
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246 if(bc_sum < 1.0 - EPSILON || bc_sum > 1.0 + EPSILON) {
|
nuclear@9
|
247 return false;
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nuclear@12
|
248 bc *= 1.2;
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nuclear@9
|
249 }
|
nuclear@2
|
250
|
nuclear@2
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251 sp->t = t;
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nuclear@9
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252 sp->pos = pt;
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nuclear@21
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253 sp->norm = normalize(face->v[0].normal * bc.x + face->v[1].normal * bc.y + face->v[2].normal * bc.z);
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nuclear@9
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254 sp->obj = face;
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nuclear@12
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255 sp->dbg = bc;
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nuclear@2
|
256 return true;
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nuclear@2
|
257 }
|
nuclear@5
|
258
|
nuclear@28
|
259 bool intersect_aabb(struct Ray ray, struct AABBox aabb)
|
nuclear@28
|
260 {
|
nuclear@28
|
261 if(ray.origin.x >= aabb.min.x && ray.origin.y >= aabb.min.y && ray.origin.z >= aabb.min.z &&
|
nuclear@28
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262 ray.origin.x < aabb.max.x && ray.origin.y < aabb.max.y && ray.origin.z < aabb.max.z) {
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nuclear@28
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263 return true;
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nuclear@28
|
264 }
|
nuclear@28
|
265
|
nuclear@29
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266 float4 bbox[2] = {
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nuclear@29
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267 aabb.min.x, aabb.min.y, aabb.min.z, 0,
|
nuclear@29
|
268 aabb.max.x, aabb.max.y, aabb.max.z, 0
|
nuclear@29
|
269 };
|
nuclear@28
|
270
|
nuclear@28
|
271 int xsign = (int)(ray.dir.x < 0.0);
|
nuclear@28
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272 float invdirx = 1.0 / ray.dir.x;
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nuclear@28
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273 float tmin = (bbox[xsign].x - ray.origin.x) * invdirx;
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nuclear@28
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274 float tmax = (bbox[1 - xsign].x - ray.origin.x) * invdirx;
|
nuclear@28
|
275
|
nuclear@28
|
276 int ysign = (int)(ray.dir.y < 0.0);
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nuclear@28
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277 float invdiry = 1.0 / ray.dir.y;
|
nuclear@28
|
278 float tymin = (bbox[ysign].y - ray.origin.y) * invdiry;
|
nuclear@28
|
279 float tymax = (bbox[1 - ysign].y - ray.origin.y) * invdiry;
|
nuclear@28
|
280
|
nuclear@28
|
281 if(tmin > tymax || tymin > tmax) {
|
nuclear@28
|
282 return false;
|
nuclear@28
|
283 }
|
nuclear@28
|
284
|
nuclear@28
|
285 if(tymin > tmin) tmin = tymin;
|
nuclear@28
|
286 if(tymax < tmax) tmax = tymax;
|
nuclear@28
|
287
|
nuclear@28
|
288 int zsign = (int)(ray.dir.z < 0.0);
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nuclear@28
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289 float invdirz = 1.0 / ray.dir.z;
|
nuclear@28
|
290 float tzmin = (bbox[zsign].z - ray.origin.z) * invdirz;
|
nuclear@28
|
291 float tzmax = (bbox[1 - zsign].z - ray.origin.z) * invdirz;
|
nuclear@28
|
292
|
nuclear@28
|
293 if(tmin > tzmax || tzmin > tmax) {
|
nuclear@28
|
294 return false;
|
nuclear@28
|
295 }
|
nuclear@28
|
296
|
nuclear@29
|
297 return tmin < 1.0 && tmax > 0.0;
|
nuclear@28
|
298 }
|
nuclear@28
|
299
|
nuclear@8
|
300 float4 reflect(float4 v, float4 n)
|
nuclear@5
|
301 {
|
nuclear@23
|
302 return 2.0f * dot(v, n) * n - v;
|
nuclear@5
|
303 }
|
nuclear@8
|
304
|
nuclear@8
|
305 float4 transform(float4 v, global const float *xform)
|
nuclear@8
|
306 {
|
nuclear@8
|
307 float4 res;
|
nuclear@8
|
308 res.x = v.x * xform[0] + v.y * xform[4] + v.z * xform[8] + xform[12];
|
nuclear@8
|
309 res.y = v.x * xform[1] + v.y * xform[5] + v.z * xform[9] + xform[13];
|
nuclear@8
|
310 res.z = v.x * xform[2] + v.y * xform[6] + v.z * xform[10] + xform[14];
|
nuclear@12
|
311 res.w = 0.0;
|
nuclear@8
|
312 return res;
|
nuclear@8
|
313 }
|
nuclear@8
|
314
|
nuclear@16
|
315 void transform_ray(struct Ray *ray, global const float *xform, global const float *invtrans)
|
nuclear@8
|
316 {
|
nuclear@16
|
317 ray->origin = transform(ray->origin, xform);
|
nuclear@16
|
318 ray->dir = transform(ray->dir, invtrans);
|
nuclear@8
|
319 }
|
nuclear@9
|
320
|
nuclear@12
|
321 float4 calc_bary(float4 pt, global const struct Face *face, float4 norm)
|
nuclear@9
|
322 {
|
nuclear@12
|
323 float4 bc = (float4)(0, 0, 0, 0);
|
nuclear@9
|
324
|
nuclear@12
|
325 // calculate area of the whole triangle
|
nuclear@12
|
326 float4 v1 = face->v[1].pos - face->v[0].pos;
|
nuclear@12
|
327 float4 v2 = face->v[2].pos - face->v[0].pos;
|
nuclear@12
|
328 float4 xv1v2 = cross(v1, v2);
|
nuclear@12
|
329
|
nuclear@16
|
330 float area = fabs(dot(xv1v2, norm)) * 0.5;
|
nuclear@9
|
331 if(area < EPSILON) {
|
nuclear@9
|
332 return bc;
|
nuclear@9
|
333 }
|
nuclear@9
|
334
|
nuclear@9
|
335 float4 pv0 = face->v[0].pos - pt;
|
nuclear@9
|
336 float4 pv1 = face->v[1].pos - pt;
|
nuclear@9
|
337 float4 pv2 = face->v[2].pos - pt;
|
nuclear@9
|
338
|
nuclear@12
|
339 // calculate the area of each sub-triangle
|
nuclear@12
|
340 float4 x12 = cross(pv1, pv2);
|
nuclear@12
|
341 float4 x20 = cross(pv2, pv0);
|
nuclear@12
|
342 float4 x01 = cross(pv0, pv1);
|
nuclear@12
|
343
|
nuclear@16
|
344 float a0 = fabs(dot(x12, norm)) * 0.5;
|
nuclear@16
|
345 float a1 = fabs(dot(x20, norm)) * 0.5;
|
nuclear@16
|
346 float a2 = fabs(dot(x01, norm)) * 0.5;
|
nuclear@9
|
347
|
nuclear@9
|
348 bc.x = a0 / area;
|
nuclear@9
|
349 bc.y = a1 / area;
|
nuclear@9
|
350 bc.z = a2 / area;
|
nuclear@9
|
351 return bc;
|
nuclear@9
|
352 }
|
nuclear@19
|
353
|
nuclear@19
|
354 float mean(float4 v)
|
nuclear@19
|
355 {
|
nuclear@19
|
356 return native_divide(v.x + v.y + v.z, 3.0);
|
nuclear@19
|
357 }
|