Make the last few global constants part of the model.

4 files changed, 43 insertions, 14 deletions

diff --git a/akamaru.c b/akamaru.c
index 76f0058..9e5f8b8 100644
--- a/akamaru.c
+++ b/akamaru.c
@@ -6,10 +6,11 @@
  *
  * TODO:
  *
- * - Add code to add boxes
  * - Add circle object
  * - Try out this idea: make constraint solver take mean of all
  *   corrections at the end instead of meaning as it goes.
+ * - Consider a size, or radius attribute for objects.
+ * - Make a gravitation object - initialized with a vector or just a point.
  */
 
 #include <glib.h>
@@ -20,10 +21,6 @@
 
 #include "akamaru.h"
 
-const double elasticity = 0.7;
-const double friction = 8;
-const double gravity = 50;
-
 void
 object_init (Object *object, double x, double y, double mass)
 {
@@ -174,13 +171,13 @@ model_accumulate_forces (Model *model)
   for (i = 0; i < model->num_objects; i++) {
     /* Gravity */
     model->objects[i].force.x = 0;
-    model->objects[i].force.y = gravity * model->objects[i].mass;
+    model->objects[i].force.y = model->gravity * model->objects[i].mass;
 
     /* Friction */
     v.x = model->objects[i].position.x - model->objects[i].previous_position.x;
     v.y = model->objects[i].position.y - model->objects[i].previous_position.y;
-    model->objects[i].force.x -= v.x * friction;
-    model->objects[i].force.y -= v.y * friction;
+    model->objects[i].force.x -= v.x * model->friction;
+    model->objects[i].force.y -= v.y * model->friction;
   }
 
   for (i = 0; i < model->num_springs; i++) {
@@ -291,7 +288,7 @@ polygon_contains_point (Polygon *polygon, Point *point)
 }
 
 static void
-polygon_reflect_object (Polygon *polygon, Object *object)
+polygon_reflect_object (Polygon *polygon, Object *object, double elasticity)
 {
   int i, edge;
   double d, distance;
@@ -327,7 +324,7 @@ model_constrain_polygon (Model *model, Polygon *polygon)
 
   for (i = 0; i < model->num_objects; i++) {
     if (polygon_contains_point (polygon, &model->objects[i].position))
-      polygon_reflect_object (polygon, &model->objects[i]);
+      polygon_reflect_object (polygon, &model->objects[i], model->elasticity);
   }
 }
 
@@ -435,7 +432,7 @@ model_step (Model *model, double delta_t)
 
   model_accumulate_forces (model);
   model_integrate (model, delta_t);
-  for (i = 0; i < 20; i++)
+  for (i = 0; i < model->constrain_iterations; i++)
     model_constrain (model);
 
   model->theta += delta_t;
diff --git a/akamaru.h b/akamaru.h
index 77f8d58..c9296f9 100644
--- a/akamaru.h
+++ b/akamaru.h
@@ -91,8 +91,12 @@ struct _Model {
   Anchor *anchors;
   int num_polygons;
   Polygon *polygons;
+
   double k;
   double friction;
+  double elasticity;
+  double gravity;
+  int constrain_iterations;
 
   Anchor mouse_anchor;
 
diff --git a/dock.c b/dock.c
index f462406..1ec0ea2 100644
--- a/dock.c
+++ b/dock.c
@@ -36,8 +36,8 @@ timeout_callback (gpointer data)
 		     closure->model.objects[i + 1].position.y + 0.5);
   }
 
-  for (i = 0; i < 4; i++)
-    model_step (&closure->model, 0.03);
+  for (i = 0; i < 6; i++)
+    model_step (&closure->model, 0.01);
 
   return TRUE;
 }
@@ -96,6 +96,12 @@ model_init_dock (Model *model, int num_items,
   model->num_anchors = 1;
   model->k = 0.1;
 
+  model->elasticity = 0.9;
+  model->friction = 150;
+  model->gravity = 50;
+  model->k = 0.8;
+  model->constrain_iterations = 8;
+
   model->polygons = g_new (Polygon, 1);
   model->num_polygons = 1;
   polygon_init_enclosing_rectangle (&model->polygons[0],
@@ -115,7 +121,7 @@ model_init_dock (Model *model, int num_items,
 
   for (i = 1; i < num_objects; i++, object++) {
     object_init (&model->objects[i],
-		 left_edge + (i - 1) * spread, height - 100, 1);
+		 left_edge + (i - 1) * spread, height - 100, 10);
     spring_init (spring++, &model->objects[0], object, spacing);
     for (j = 1; j < num_objects - i; j++) {
       spacer_init (spacer++, object, object + j, spacing);
diff --git a/main.c b/main.c
index 15fbce4..5864191 100644
--- a/main.c
+++ b/main.c
@@ -17,6 +17,16 @@
 #include "akamaru.h"
 
 static void
+model_init_constants (Model *model)
+{
+  model->elasticity = 0.7;
+  model->friction = 8;
+  model->gravity = 50;
+  model->k = 0.1;
+  model->constrain_iterations = 20;
+}
+
+static void
 model_init_polygons (Model *model)
 {
   const int num_polygons = 5;
@@ -46,6 +56,8 @@ model_init_snake (Model *model)
   model->num_objects = num_objects;
   model->sticks = g_new (Stick, num_sticks);
   model->num_sticks = num_sticks;
+
+  model_init_constants (model);
   model_init_polygons (model);
 
   for (i = 0; i < num_objects; i++) {
@@ -78,6 +90,8 @@ model_init_rope (Model *model)
   model->num_objects = num_objects;
   model->sticks = g_new (Stick, num_sticks);
   model->num_sticks = num_sticks;
+
+  model_init_constants (model);
   model_init_polygons (model);
 
   for (i = 0; i < num_objects; i++) {
@@ -110,6 +124,8 @@ model_init_curtain (Model *model)
   model->num_sticks = num_sticks;
   model->offsets = g_new (Offset, 1);
   model->num_offsets = 1;
+
+  model_init_constants (model);
   model_init_polygons (model);
 
   model->offsets[0].num_objects = num_ropes;
@@ -157,6 +173,8 @@ model_init_grid (Model *model)
   model->num_strings = num_strings;
   model->offsets = g_new (Offset, 1);
   model->num_offsets = 1;
+
+  model_init_constants (model);
   model_init_polygons (model);
 
   model->offsets[0].num_objects = num_ropes;
@@ -198,6 +216,8 @@ model_init_molecule (Model *model)
   model->num_springs = num_springs;
   model->k = 2;
 
+  model_init_constants (model);
+
   for (i = 0; i < num_objects; i++)
     object_init (&model->objects[i], 200 + i * 20, 200, 0);
 
@@ -232,6 +252,7 @@ model_init_wobbly (Model *model)
   model->num_offset_springs = num_offset_springs;
   model->k = 4.5;
 
+  model_init_constants (model);
   model_init_polygons (model);
 
   object = model->objects;
@@ -277,6 +298,7 @@ model_init_dock (Model *model)
   model->num_anchors = 1;
   model->k = 0.1;
 
+  model_init_constants (model);
   model->polygons = g_new (Polygon, 1);
   model->num_polygons = 1;
   polygon_init_enclosing_rectangle (&model->polygons[0], 10, 10, 700, 500);