BGE patch: new force field constraint actuator

A new type of constraint actuator is available: Force field.
It provides a very similar service to the Fh material feature
but with some specificities:
- It is defined at the object level: each object can have 
  different settings and you don't need to use material.
- It can be applied in all 6 directions and not just -Z.
- It can be enabled/disabled easily (it's an actuator).
- You can have multiple force fields active at the same time
  on the same object in different direction (think of a 
  space ship in a tunnel with a repulsive force field
  on each wall).
- You can have a different damping for the rotation.

Besides that it provides the same dynamic behavior and the 
parameters are self explanatory.
It works by adapting the linear and angular velocity: the
dynamic is independent of the mass. It is compatible with
all other motion actuators.

Note: linear and anysotropic friction is not yet implemented,
the only friction will come from the object damping parameters. 
Support for friction will be added in a future revision.

1 files changed, 2 insertions, 0 deletions

diff --git a/source/blender/makesdna/DNA_actuator_types.h b/source/blender/makesdna/DNA_actuator_types.h
index 2487216f764..0af1ec0a2c7 100644
--- a/source/blender/makesdna/DNA_actuator_types.h
+++ b/source/blender/makesdna/DNA_actuator_types.h
@@ -369,6 +369,7 @@ typedef struct FreeCamera {
 #define ACT_CONST_PERMANENT 256
 #define ACT_CONST_DISTANCE	512
 #define ACT_CONST_LOCAL     1024
+#define ACT_CONST_DOROTFH	2048
 
 /* constraint mode */
 #define ACT_CONST_DIRPX		1
@@ -382,6 +383,7 @@ typedef struct FreeCamera {
 #define ACT_CONST_TYPE_LOC	0
 #define ACT_CONST_TYPE_DIST	1
 #define ACT_CONST_TYPE_ORI	2
+#define ACT_CONST_TYPE_FH   3
 
 /* editObjectActuator->type */
 #define ACT_EDOB_ADD_OBJECT		0