archive/blender-archive
Archived
1
1
Fork 0
Code Pull Requests Packages Activity

*ray<->bb hit optimization... just to make it "slightly" faster :P

Browse Source 
Based on Tactical Optimization of Ray/Box Intersection, by Graham Fyffe
[http://tog.acm.org/resources/RTNews/html/rtnv21n1.html#art9]

*for now it breaks shrinkwrap or other stuff that relies on sphere-raycast of BLI_kdopbvh.
This commit is contained in:
Andre Susano Pinto
2009-06-11 18:25:29 +00:00
parent 49479ef910
commit d198480db8
2 changed files with 42 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

39
source/blender/blenlib/intern/BLI_kdopbvh.c
View File

@@ -101,6 +101,8 @@ typedef struct BVHRayCastData
BVHTreeRay ray;
float ray_dot_axis[13];
float idot_axis[13];
int index[6];
BVHTreeRayHit hit;
} BVHRayCastData;
@@ -1404,6 +1406,7 @@ int BLI_bvhtree_find_nearest(BVHTree *tree, const float *co, BVHTreeNearest *nea
* raycast is done by performing a DFS on the BVHTree and saving the closest hit
*/
//Determines the distance that the ray must travel to hit the bounding volume of the given node
static float ray_nearest_hit(BVHRayCastData *data, BVHNode *node)
{
@@ -1443,13 +1446,40 @@ static float ray_nearest_hit(BVHRayCastData *data, BVHNode *node)
return low;
}
//Determines the distance that the ray must travel to hit the bounding volume of the given node
//Based on Tactical Optimization of Ray/Box Intersection, by Graham Fyffe
//[http://tog.acm.org/resources/RTNews/html/rtnv21n1.html#art9]
//
//TODO this doens't has data->ray.radius in consideration
static float fast_ray_nearest_hit(const BVHRayCastData *data, const BVHNode *node)
{
const float *bv = node->bv;
float dist;
float t1x = (bv[data->index[0]] - data->ray.origin[0]) * data->idot_axis[0];
float t2x = (bv[data->index[1]] - data->ray.origin[0]) * data->idot_axis[0];
float t1y = (bv[data->index[2]] - data->ray.origin[1]) * data->idot_axis[1];
float t2y = (bv[data->index[3]] - data->ray.origin[1]) * data->idot_axis[1];
float t1z = (bv[data->index[4]] - data->ray.origin[2]) * data->idot_axis[2];
float t2z = (bv[data->index[5]] - data->ray.origin[2]) * data->idot_axis[2];
if(t1x > t2y || t2x < t1y || t1x > t2z || t2x < t1z || t1y > t2z || t2y < t1z) return FLT_MAX;
if(t2x < 0.0 || t2y < 0.0 || t2z < 0.0) return FLT_MAX;
if(t1x > data->hit.dist || t1y > data->hit.dist || t1z > data->hit.dist) return FLT_MAX;
dist = t1x;
if (t1y > dist) dist = t1y;
if (t1z > dist) dist = t1z;
return dist;
}
static void dfs_raycast(BVHRayCastData *data, BVHNode *node)
{
int i;
//ray-bv is really fast.. and simple tests revealed its worth to test it
//before calling the ray-primitive functions
float dist = ray_nearest_hit(data, node);
float dist = fast_ray_nearest_hit(data, node);
if(dist >= data->hit.dist) return;
if(node->totnode == 0)
@@ -1503,9 +1533,16 @@ int BLI_bvhtree_ray_cast(BVHTree *tree, const float *co, const float *dir, float
for(i=0; i<3; i++)
{
data.ray_dot_axis[i] = INPR( data.ray.direction, KDOP_AXES[i]);
data.idot_axis[i] = 1.0f / data.ray_dot_axis[i];
if(fabs(data.ray_dot_axis[i]) < FLT_EPSILON)
{
data.ray_dot_axis[i] = 0.0;
}
data.index[2*i] = data.idot_axis[i] < 0.0 ? 1 : 0;
data.index[2*i+1] = 1 - data.index[2*i];
data.index[2*i] += 2*i;
data.index[2*i+1] += 2*i;
}

7
source/blender/render/intern/source/rayshade.c
View File

@@ -177,8 +177,8 @@ RayObject* makeraytree_object(Render *re, ObjectInstanceRen *obi)
//Create Ray cast accelaration structure
//TODO dynamic ocres
raytree = obr->raytree = RE_rayobject_octree_create( re->r.ocres, faces );
// raytree = obr->raytree = RE_rayobject_bvh_create( faces );
// raytree = obr->raytree = RE_rayobject_octree_create( re->r.ocres, faces );
raytree = obr->raytree = RE_rayobject_bvh_create( faces );
face = obr->rayfaces = (RayFace*)MEM_callocN(faces*sizeof(RayFace), "ObjectRen faces");
obr->rayobi = obi;
@@ -284,7 +284,8 @@ static void makeraytree_single(Render *re)
}
//Create raytree
raytree = re->raytree = RE_rayobject_octree_create(re->r.ocres, faces);
// raytree = re->raytree = RE_rayobject_octree_create(re->r.ocres, faces);
raytree = re->raytree = RE_rayobject_bvh_create(faces);
face = re->rayfaces = (RayFace*)MEM_callocN(faces*sizeof(RayFace), "Render ray faces");
for(obi=re->instancetable.first; obi; obi=obi->next)