Working on clouds walking

src/rendering/clouds/clo_lighting.c

@@ -0,0 +1,2 @@
+#include "clo_lighting.h"
+

src/rendering/clouds/clo_lighting.h

@@ -0,0 +1,30 @@
+#ifndef _PAYSAGES_CLOUDS_LIGHTING_H_
+#define _PAYSAGES_CLOUDS_LIGHTING_H_
+
+#include "public.h"
+#include "../tools/euclid.h"
+
+/**
+ * Cloud lighting helpers.
+ */
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+/*
+ * Bind fake lighting functions to a renderer.
+ */
+void cloudsBindFakeLightingToRenderer(CloudsRenderer* renderer);
+
+/*
+ * Bind real lighting functions to a renderer.
+ */
+void cloudsBindRealLightingToRenderer(CloudsRenderer* renderer);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/rendering/clouds/clo_walking.c

@@ -136,8 +136,8 @@ int cloudsGetLayerPrimarySegments(Renderer* renderer, CloudsLayerDefinition* lay
                 /* exiting the cloud */
                 segment_length += step_length;
 
-                out_segments->enter = segment_start;
+                out_segments->entry_point = segment_start;
-                out_segments->exit = walker;
+                out_segments->exit_point = walker;
                 out_segments->length = segment_length;
                 out_segments++;
                 if (++segment_count >= max_segments)
@@ -155,3 +155,7 @@ int cloudsGetLayerPrimarySegments(Renderer* renderer, CloudsLayerDefinition* lay
 
     return segment_count;
 }
+
+int cloudsGetLayerSecondarySampling(Renderer* renderer, CloudsLayerDefinition* layer, CloudPrimarySegment* segment, int max_control_points, CloudSecondaryControlPoint* out_control_points)
+{
+}

src/rendering/clouds/clo_walking.h

@@ -5,7 +5,7 @@
 #include "../tools/euclid.h"
 
 /**
- * Functions to walk through a cloud layer.
+ * Functions to walk through a cloud layer (sampling).
  */
 
 #ifdef __cplusplus
@@ -15,11 +15,25 @@ extern "C"
 
 typedef struct
 {
-    Vector3 enter;
+    Vector3 entry_point;
-    Vector3 exit;
+    Vector3 exit_point;
     double length;
 } CloudPrimarySegment;
 
+typedef struct
+{
+    /** Distance factor of the control point from the segment start */
+    double distance;
+    /** Location of the control point */
+    Vector3 location;
+    /** Global density at the control point (no edge noise applied) */
+    double global_density;
+    /** Particle dentisy at the control point, using edge noise */
+    double particle_density;
+    /** Estimated distance to nearest cloud exit */
+    double nearest_exit_distance;
+} CloudSecondaryControlPoint;
+
 /**
  * Optimize the search limits in a layer.
  *
@@ -38,11 +52,23 @@ int cloudsOptimizeWalkingBounds(CloudsLayerDefinition* layer, Vector3* start, Ve
  * @param start Start position of the lookup
  * @param end End position of the lookup
  * @param max_segments Maximum number of segments to collect
- * @param out_segments Allocated space to fill found segments
+ * @param out_segments Allocated space to fill found segments (must be at least 'max_segments' long)
  * @return Number of segments found
  */
 int cloudsGetLayerPrimarySegments(Renderer* renderer, CloudsLayerDefinition* layer, Vector3 start, Vector3 end, int max_segments, CloudPrimarySegment* out_segments);
 
+/**
+ * Sample a primary segment with refined details, collecting material interaction.
+ *
+ * @param renderer The renderer environment
+ * @param layer The cloud layer
+ * @param segment The primary segment to sample
+ * @param max_control_points Maximum number of control points to sample
+ * @param out_control_points Allocated space to fill with secondary control points (must be at least 'max_control_points' long)
+ * @return Number of control points sampled
+ */
+int cloudsGetLayerSecondarySampling(Renderer* renderer, CloudsLayerDefinition* layer, CloudPrimarySegment* segment, int max_control_points, CloudSecondaryControlPoint* out_control_points);
+
 #ifdef __cplusplus
 }
 #endif

src/testing/test_clouds.c

@@ -221,18 +221,18 @@ START_TEST(test_clouds_primary_segments)
     ck_assert_int_eq(segment_count, 2);
     for (i = 0; i < segment_count; i++)
     {
-        ck_assert_double_eq(segments[i].enter.y, 0.0);
+        ck_assert_double_eq(segments[i].entry_point.y, 0.0);
-        ck_assert_double_eq(segments[i].enter.z, 0.0);
+        ck_assert_double_eq(segments[i].entry_point.z, 0.0);
-        ck_assert_double_eq(segments[i].exit.y, 0.0);
+        ck_assert_double_eq(segments[i].exit_point.y, 0.0);
-        ck_assert_double_eq(segments[i].exit.z, 0.0);
+        ck_assert_double_eq(segments[i].exit_point.z, 0.0);
     }
-    ck_assert_double_in_range(segments[0].enter.x, -0.5, 0.0);
+    ck_assert_double_in_range(segments[0].entry_point.x, -0.4, 0.0);
-    ck_assert_double_in_range(segments[0].exit.x, 0.5, 1.0);
+    ck_assert_double_in_range(segments[0].exit_point.x, 0.5, 1.0);
-    ck_assert_double_in_range(segments[0].length, 0.5, 1.5);
+    ck_assert_double_in_range(segments[0].length, 0.5, 1.3);
-    ck_assert_double_gte(segments[1].enter.x, segments[0].exit.x);
+    ck_assert_double_gte(segments[1].entry_point.x, segments[0].exit_point.x);
-    ck_assert_double_in_range(segments[1].enter.x, 0.5, 1.0);
+    ck_assert_double_in_range(segments[1].entry_point.x, 0.5, 1.0);
-    ck_assert_double_in_range(segments[1].exit.x, 1.5, 2.0);
+    ck_assert_double_in_range(segments[1].exit_point.x, 1.5, 1.9);
-    ck_assert_double_in_range(segments[1].length, 0.5, 1.5);
+    ck_assert_double_in_range(segments[1].length, 0.5, 1.3);
 
     cloudsGetLayerType().callback_delete(layer);
     rendererDelete(renderer);