More F-Modifier Tweaks:

This commit started out aiming to make the "Stepped" F-Modifier (committed last night) even more useful, but ended up fixing a few other finer-points of how F-Modifiers work.

Firstly, the new stuff:
I've addded options to the Stepped F-Modifier to not affect frames before and/or after specified values, and renamed the 'start offset' to 'offset' for clarity. 

The main objective of this is to allow Stepped F-Modifiers to only affect certain time ranges, so that by layering/using multiple instances of the F-Modifier, it can be possible to have multiple stepping-sizes.

This allows for effects like:
http://www.pasteall.org/blend/2230
or in words, it provides a convenient mechanism for animators to specify whether sections of the animation is shown "on twos", "fours", or even "forty-second-ths plus a smidgen", as can be easily done with 2D.

Assorted changes to support this:
* Properly fixed up how F-Modifiers that work with time, evaluate the time to evaluate the curve at. Now layered time effects like this should be possible in a much nicer way.

* Added proper value range validation/clamping to many properties. There are still a lot more that need checking, but at least more properties now do "the right thing". 

1 files changed, 12 insertions, 1 deletions

diff --git a/source/blender/makesdna/DNA_anim_types.h b/source/blender/makesdna/DNA_anim_types.h
index 44727218f4f..83f68758da9 100644
--- a/source/blender/makesdna/DNA_anim_types.h
+++ b/source/blender/makesdna/DNA_anim_types.h
@@ -236,9 +236,20 @@ typedef enum eFMod_Noise_Modifications {
 /* stepped modifier data */
 typedef struct FMod_Stepped {
 	float step_size;				/* Number of frames each interpolated value should be held */
-	float start;					/* Reference frame number that stepping starts from */
+	float offset;					/* Reference frame number that stepping starts from */
+	
+	float start_frame;				/* start frame of the frame range that modifier works in */				
+	float end_frame;				/* end frame of the frame range that modifier works in */
+	
+	int flag;						/* various settings */	
 } FMod_Stepped;
 
+/* stepped modifier range flags */
+typedef enum eFMod_Stepped_Flags {
+	FCM_STEPPED_NO_BEFORE 	= (1<<0),	/* don't affect frames before the start frame */
+	FCM_STEPPED_NO_AFTER 	= (1<<1),	/* don't affect frames after the end frame */
+} eFMod_Stepped_Flags;
+
 /* Drivers -------------------------------------- */
 
 /* Driver Target (dtar)