Support global ambient_light.

3 files changed, 6 insertions, 1 deletions

diff --git a/libdimension/dimension/scene.h b/libdimension/dimension/scene.h
index 57ef32b..489e4e5 100644
--- a/libdimension/dimension/scene.h
+++ b/libdimension/dimension/scene.h
@@ -44,6 +44,7 @@ typedef unsigned int dmnsn_quality;
 typedef struct dmnsn_scene {
   /* World attributes */
   dmnsn_color background;         /**< Background color. */
+  dmnsn_color ambient;            /**< Global ambient color. */
   dmnsn_texture *default_texture; /**< Default object texture. */
 
   /** Camera. */
diff --git a/libdimension/raytrace.c b/libdimension/raytrace.c
index 74f4557..e6596e4 100644
--- a/libdimension/raytrace.c
+++ b/libdimension/raytrace.c
@@ -337,9 +337,11 @@ dmnsn_raytrace_light_ray(const dmnsn_raytrace_state *state,
 static void
 dmnsn_raytrace_lighting(dmnsn_raytrace_state *state)
 {
-  /* The illuminated color */
+  /* The ambient color */
   state->diffuse = TEXTURE_CALLBACK(state, finish, ambient_fn, dmnsn_black,
                                     state->pigment);
+  state->diffuse = dmnsn_color_illuminate(state->scene->ambient,
+                                          state->diffuse);
 
   if (!TEXTURE_HAS_CALLBACK(state, finish, diffuse_fn)
       && !TEXTURE_HAS_CALLBACK(state, finish, specular_fn))
diff --git a/libdimension/scene.c b/libdimension/scene.c
index fc5bb92..9eca7b7 100644
--- a/libdimension/scene.c
+++ b/libdimension/scene.c
@@ -32,6 +32,8 @@ dmnsn_new_scene()
 {
   dmnsn_scene *scene = dmnsn_malloc(sizeof(dmnsn_scene));
 
+  scene->background      = dmnsn_black;
+  scene->ambient         = dmnsn_white;
   scene->default_texture = dmnsn_new_texture();
   scene->camera          = NULL;
   scene->canvas          = NULL;