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authorTavian Barnes <tavianator@gmail.com>2010-03-02 01:30:52 -0500
committerTavian Barnes <tavianator@gmail.com>2010-03-02 01:30:52 -0500
commite3805176cd1e77ccb32410cbd0a4e454dd34b509 (patch)
treef32c8ac0ac43cd866a8da5a89e51d5a05b01051a /libdimension
parent0e6d09432d7c22c8c0f3acedefc1afac67624a8d (diff)
downloaddimension-e3805176cd1e77ccb32410cbd0a4e454dd34b509.tar.xz
Handle nested refractive objects correctly.
Diffstat (limited to 'libdimension')
-rw-r--r--libdimension/raytrace.c35
1 files changed, 24 insertions, 11 deletions
diff --git a/libdimension/raytrace.c b/libdimension/raytrace.c
index 734ff72..a85d8e6 100644
--- a/libdimension/raytrace.c
+++ b/libdimension/raytrace.c
@@ -211,6 +211,8 @@ dmnsn_raytrace_scene_multithread_thread(void *ptr)
*/
typedef struct dmnsn_raytrace_state {
+ const struct dmnsn_raytrace_state *parent;
+
const dmnsn_scene *scene;
const dmnsn_intersection *intersection;
dmnsn_bvst *bvst;
@@ -238,9 +240,10 @@ dmnsn_raytrace_scene_impl(dmnsn_progress *progress, dmnsn_scene *scene,
unsigned int index, unsigned int threads)
{
dmnsn_raytrace_state state = {
- .scene = scene,
- .bvst = bvst,
- .ior = 1.0
+ .parent = NULL,
+ .scene = scene,
+ .bvst = bvst,
+ .ior = 1.0
};
unsigned int width = scene->canvas->x;
@@ -306,7 +309,12 @@ dmnsn_line_add_epsilon(dmnsn_line l)
? (*ITEXTURE(state)->telem->fn)(ITEXTURE(state)->telem, __VA_ARGS__) \
: (CAN_CALL(DTEXTURE(state), telem, fn) \
? (*DTEXTURE(state)->telem->fn)(DTEXTURE(state)->telem, __VA_ARGS__) \
- : def)); \
+ : def));
+
+#define IOR(state) \
+ ((state)->intersection->interior \
+ ? (state)->intersection->interior->ior \
+ : 1.0)
static void
dmnsn_raytrace_pigment(dmnsn_raytrace_state *state)
@@ -440,18 +448,23 @@ dmnsn_raytrace_translucency(dmnsn_raytrace_state *state)
dmnsn_line trans_ray = dmnsn_new_line(state->r, state->intersection->ray.n);
trans_ray = dmnsn_line_add_epsilon(trans_ray);
- dmnsn_raytrace_state recursive_state = *state;
-
- double iorr = state->ior; /* ior ratio */
-
dmnsn_vector r = dmnsn_vector_normalize(trans_ray.n);
dmnsn_vector n = state->intersection->normal;
- if (state->intersection->interior && dmnsn_vector_dot(r, n) < 0.0) {
- iorr /= state->intersection->interior->ior;
- recursive_state.ior = state->intersection->interior->ior;
+ dmnsn_raytrace_state recursive_state = *state;
+
+ if (dmnsn_vector_dot(r, n) < 0.0) {
+ /* We are entering an object */
+ recursive_state.ior = IOR(state);
+ recursive_state.parent = state;
+ } else {
+ /* We are leaving an object */
+ recursive_state.ior = state->parent ? state->parent->ior : 1.0;
+ recursive_state.parent = state->parent ? state->parent->parent : NULL;
}
+ double iorr = state->ior/recursive_state.ior; /* ior ratio */
+
double c1 = -dmnsn_vector_dot(r, n);
double c2 = 1.0 - iorr*iorr*(1.0 - c1*c1);
if (c2 <= 0.0) {