Cloth refactor: Remove goal springs and some other cleanup

This removes the goal springs, in favor of simply calculating the goal forces on the vertices directly. The vertices already store all the necessary data for the goal forces, thus the springs were redundant, and just defined both ends as being the same vertex.

The main advantage of removing the goal springs, is an increase in flexibility, allowing us to much more nicely do some neat dynamic stuff with the goals/pins, such as animated vertex weights. But this also has the advantage of simpler code, and a slightly reduced memory footprint.

This also removes the `f`, `dfdx` and `dfdv` fields from the `ClothSpring` struct, as that data is only used by the solver, and is re-computed on each step, and thus does not need to be stored throughout the simulation.

Reviewers: sergey

Reviewed By: sergey

Tags: #physics

Differential Revision: https://developer.blender.org/D2514

1 files changed, 0 insertions, 6 deletions

diff --git a/source/blender/blenkernel/BKE_cloth.h b/source/blender/blenkernel/BKE_cloth.h
index 36330242f18..6c517bd02df 100644
--- a/source/blender/blenkernel/BKE_cloth.h
+++ b/source/blender/blenkernel/BKE_cloth.h
@@ -136,9 +136,6 @@ typedef struct ClothSpring {
 	float	restlen;	/* The original length of the spring.	*/
 	int	type;		/* types defined in BKE_cloth.h ("springType") */
 	int	flags; 		/* defined in BKE_cloth.h, e.g. deactivated due to tearing */
-	float dfdx[3][3];
-	float dfdv[3][3];
-	float f[3];
 	float 	stiffness;	/* stiffness factor from the vertex groups */
 	float editrestlen;
 	
@@ -240,9 +237,6 @@ void bvhselftree_update_from_cloth(struct ClothModifierData *clmd, bool moving);
 // needed for button_object.c
 void cloth_clear_cache (struct Object *ob, struct ClothModifierData *clmd, float framenr );
 
-// needed for cloth.c
-int cloth_add_spring (struct ClothModifierData *clmd, unsigned int indexA, unsigned int indexB, float restlength, int spring_type);
-
 void cloth_parallel_transport_hair_frame(float mat[3][3], const float dir_old[3], const float dir_new[3]);
 
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