FCurve Modifiers - "Limits" Modifier:

This new modifier clamps the values of the F-Curve to lie within specified bounds, much like Limit Location/Rotation/Scale constraints do. You can limit by time range(s) and/or value range(s).

4 files changed, 133 insertions, 14 deletions

diff --git a/source/blender/blenkernel/intern/fcurve.c b/source/blender/blenkernel/intern/fcurve.c
index 3e1b6f29403..2783c135cb9 100644
--- a/source/blender/blenkernel/intern/fcurve.c
+++ b/source/blender/blenkernel/intern/fcurve.c
@@ -1135,6 +1135,43 @@ static FModifierTypeInfo FMI_MODNAME = {
 };
 #endif
 
+/* Utilities For F-Curve Modifiers ---------------------- */
+
+/* Recalculate the F-Curve at evaltime, as modified by the given F-Curve */
+// TODO: this isn't really such an elegant solution for time-modifying F-Modifiers, but it gets too difficult otherwise for now...
+static float fcm_reevaluate_fcurve (FCurve *fcu, FModifier *fcm, float cvalue, float evaltime)
+{ 
+	ListBase modifiers = {NULL, NULL};
+	float new_value = 0.0f;
+	
+	/* sanity checking */
+	if ELEM(NULL, fcu, fcm)
+		return cvalue;
+	
+	/* unlink given modifier from previous modifiers, keeping the previous ones on the F-Curve,
+	 * but ones after off the F-Curve (so that we avoid the infinitely re-entrant situation).
+	 */
+	modifiers.first= fcm;
+	modifiers.last= fcu->modifiers.last;
+	
+	if (fcm->prev) {
+		fcm->prev->next= NULL;
+		fcu->modifiers.last= fcm->prev;
+	}
+	else
+		fcu->modifiers.first= fcu->modifiers.last= NULL;
+	fcm->prev= NULL;
+	
+	/* re-enter the evaluation loop (but without the burden of evaluating any modifiers, so 'should' be relatively quick) */
+	new_value= evaluate_fcurve(fcu, evaltime);
+	
+	/* restore modifiers (don't assume everything is still ok after being re-entrant) */
+	addlisttolist(&fcu->modifiers, &modifiers);
+	
+	/* return the new value */
+	return new_value;
+}
+
 /* Generator F-Curve Modifier --------------------------- */
 
 /* Generators available:
@@ -1547,9 +1584,7 @@ static void fcm_cycles_new_data (void *mdata)
 static void fcm_cycles_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
 {
 	FMod_Cycles *data= (FMod_Cycles *)fcm->data;
-	ListBase mods = {NULL, NULL};
 	float prevkey[2], lastkey[2], cycyofs=0.0f;
-	float new_value;
 	short side=0, mode=0;
 	int cycles=0;
 	
@@ -1644,17 +1679,8 @@ static void fcm_cycles_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, flo
 		if (evaltime < ofs) evaltime += cycdx;
 	}
 	
-	
-	/* store modifiers after (and including ourself) before recalculating curve with new evaltime */
-	mods= fcu->modifiers;
-	fcu->modifiers.first= fcu->modifiers.last= NULL;
-	
-	/* re-enter the evaluation loop (but without the burden of evaluating any modifiers, so 'should' be relatively quick) */
-	new_value= evaluate_fcurve(fcu, evaltime);
-	
-	/* restore modifiers, and set new value (don't assume everything is still ok after being re-entrant) */
-	fcu->modifiers= mods;
-	*cvalue= new_value + cycyofs;
+	/* reevaluate F-Curve at the new time that we've decided on */
+	*cvalue= fcm_reevaluate_fcurve(fcu, fcm, *cvalue, evaltime) + cycyofs;
 }
 
 static FModifierTypeInfo FMI_CYCLES = {
@@ -1762,6 +1788,39 @@ static FModifierTypeInfo FMI_PYTHON = {
 };
 
 
+/* Limits F-Curve Modifier --------------------------- */
+
+static void fcm_limits_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
+{
+	FMod_Limits *data= (FMod_Limits *)fcm->data;
+	
+	/* time limits first */
+	if ((data->flag & FCM_LIMIT_XMIN) && (evaltime < data->rect.xmin))
+		*cvalue= fcm_reevaluate_fcurve(fcu, fcm, *cvalue, data->rect.xmin);
+	if ((data->flag & FCM_LIMIT_XMAX) && (evaltime > data->rect.xmax))
+		*cvalue= fcm_reevaluate_fcurve(fcu, fcm, *cvalue, data->rect.xmax);
+	
+	/* value limits now */
+	if ((data->flag & FCM_LIMIT_YMIN) && (*cvalue < data->rect.ymin))
+		*cvalue= data->rect.ymin;
+	if ((data->flag & FCM_LIMIT_YMAX) && (*cvalue > data->rect.ymax))
+		*cvalue= data->rect.ymax;
+}
+
+static FModifierTypeInfo FMI_LIMITS = {
+	FMODIFIER_TYPE_LIMITS, /* type */
+	sizeof(FMod_Limits), /* size */
+	FMI_TYPE_GENERATE_CURVE, /* action type */  /* XXX... err... */   
+	FMI_REQUIRES_RUNTIME_CHECK, /* requirements */
+	"Limits", /* name */
+	"FMod_Limits", /* struct name */
+	NULL, /* free data */
+	NULL, /* copy data */
+	NULL, /* new data */
+	NULL /*fcm_python_verify*/, /* verify */
+	fcm_limits_evaluate /* evaluate */
+};
+
 /* F-Curve Modifier API --------------------------- */
 /* All of the F-Curve Modifier api functions use FModifierTypeInfo structs to carry out
  * and operations that involve F-Curve modifier specific code.
@@ -1781,6 +1840,7 @@ static void fmods_init_typeinfo ()
 	fmodifiersTypeInfo[4]=  NULL/*&FMI_NOISE*/;				/* Apply-Noise F-Curve Modifier */ // XXX unimplemented
 	fmodifiersTypeInfo[5]=  NULL/*&FMI_FILTER*/;			/* Filter F-Curve Modifier */  // XXX unimplemented
 	fmodifiersTypeInfo[6]=  &FMI_PYTHON;			/* Custom Python F-Curve Modifier */
+	fmodifiersTypeInfo[7]= 	&FMI_LIMITS;			/* Limits F-Curve Modifier */
 }
 
 /* This function should be used for getting the appropriate type-info when only
diff --git a/source/blender/editors/space_graph/graph_buttons.c b/source/blender/editors/space_graph/graph_buttons.c
index a59ec1fd4c8..680273ae508 100644
--- a/source/blender/editors/space_graph/graph_buttons.c
+++ b/source/blender/editors/space_graph/graph_buttons.c
@@ -754,6 +754,43 @@ static void draw_modifier__envelope(uiBlock *block, FCurve *fcu, FModifier *fcm,
 
 /* --------------- */
 
+/* draw settings for limits modifier */
+static void draw_modifier__limits(uiBlock *block, FCurve *fcu, FModifier *fcm, int *yco, short *height, short width, short active, int rb_col)
+{
+	FMod_Limits *data= (FMod_Limits *)fcm->data;
+	const int togButWidth = 50;
+	const int textButWidth = ((width/2)-togButWidth);
+	
+	/* set the height */
+	(*height) = 90;
+	
+	/* basic settings (backdrop + some padding) */
+	//DRAW_BACKDROP((*height)); // XXX buggy...
+	
+	/* Draw Pairs of LimitToggle+LimitValue */
+	uiBlockBeginAlign(block); 
+		uiDefButBitI(block, TOGBUT, FCM_LIMIT_XMIN, B_FMODIFIER_REDRAW, "xMin", 10, *yco-30, togButWidth, 18, &data->flag, 0, 24, 0, 0, "Use minimum x value"); 
+		uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "", 10+togButWidth, *yco-30, (textButWidth-5), 18, &data->rect.xmin, -FLT_MAX, FLT_MAX, 0.1,0.5,"Lowest x value to allow"); 
+	uiBlockEndAlign(block); 
+	
+	uiBlockBeginAlign(block); 
+		uiDefButBitI(block, TOGBUT, FCM_LIMIT_XMAX, B_FMODIFIER_REDRAW, "XMax", 10+(width-(textButWidth-5)-togButWidth), *yco-30, 50, 18, &data->flag, 0, 24, 0, 0, "Use maximum x value"); 
+		uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "", 10+(width-textButWidth-5), *yco-30, (textButWidth-5), 18, &data->rect.xmax, -FLT_MAX, FLT_MAX, 0.1,0.5,"Highest x value to allow"); 
+	uiBlockEndAlign(block); 
+	
+	uiBlockBeginAlign(block); 
+		uiDefButBitI(block, TOGBUT, FCM_LIMIT_YMIN, B_FMODIFIER_REDRAW, "yMin", 10, *yco-52, togButWidth, 18, &data->flag, 0, 24, 0, 0, "Use minimum y value"); 
+		uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "", 10+togButWidth, *yco-52, (textButWidth-5), 18, &data->rect.ymin, -FLT_MAX, FLT_MAX, 0.1,0.5,"Lowest y value to allow"); 
+	uiBlockEndAlign(block);
+	
+	uiBlockBeginAlign(block); 
+		uiDefButBitI(block, TOGBUT, FCM_LIMIT_YMAX, B_FMODIFIER_REDRAW, "YMax", 10+(width-(textButWidth-5)-togButWidth), *yco-52, 50, 18, &data->flag, 0, 24, 0, 0, "Use maximum y value"); 
+		uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "", 10+(width-textButWidth-5), *yco-52, (textButWidth-5), 18, &data->rect.ymax, -FLT_MAX, FLT_MAX, 0.1,0.5,"Highest y value to allow"); 
+	uiBlockEndAlign(block); 
+}
+
+/* --------------- */
+
 static void graph_panel_modifier_draw(uiBlock *block, FCurve *fcu, FModifier *fcm, int *yco)
 {
 	FModifierTypeInfo *fmi= fmodifier_get_typeinfo(fcm);
@@ -810,6 +847,10 @@ static void graph_panel_modifier_draw(uiBlock *block, FCurve *fcu, FModifier *fc
 			case FMODIFIER_TYPE_ENVELOPE: /* Envelope */
 				draw_modifier__envelope(block, fcu, fcm, yco, &height, width, active, rb_col);
 				break;
+				
+			case FMODIFIER_TYPE_LIMITS: /* Limits */
+				draw_modifier__limits(block, fcu, fcm, yco, &height, width, active, rb_col);
+				break;
 			
 			default: /* unknown type */
 				height= 96;
diff --git a/source/blender/editors/space_graph/graph_edit.c b/source/blender/editors/space_graph/graph_edit.c
index 3aea32d64e7..52301ac1b0f 100644
--- a/source/blender/editors/space_graph/graph_edit.c
+++ b/source/blender/editors/space_graph/graph_edit.c
@@ -1647,6 +1647,7 @@ EnumPropertyItem prop_fmodifier_types[] = {
 	{FMODIFIER_TYPE_NOISE, "NOISE", "Noise", ""},
 	{FMODIFIER_TYPE_FILTER, "FILTER", "Filter", ""},
 	{FMODIFIER_TYPE_PYTHON, "PYTHON", "Python", ""},
+	{FMODIFIER_TYPE_LIMITS, "LIMITS", "Limits", ""},
 	{0, NULL, NULL, NULL}
 };
 
diff --git a/source/blender/makesdna/DNA_anim_types.h b/source/blender/makesdna/DNA_anim_types.h
index 9112a714857..5956c65046b 100644
--- a/source/blender/makesdna/DNA_anim_types.h
+++ b/source/blender/makesdna/DNA_anim_types.h
@@ -46,7 +46,8 @@ enum {
 	FMODIFIER_TYPE_CYCLES,
 	FMODIFIER_TYPE_NOISE,		/* unimplemented - generate variations using some basic noise generator... */
 	FMODIFIER_TYPE_FILTER,		/* unimplemented - for applying: fft, high/low pass filters, etc. */
-	FMODIFIER_TYPE_PYTHON,		
+	FMODIFIER_TYPE_PYTHON,	
+	FMODIFIER_TYPE_LIMITS,
 	
 	/* NOTE: all new modifiers must be added above this line */
 	FMODIFIER_NUM_TYPES
@@ -149,6 +150,22 @@ typedef struct FMod_Python {
 	IDProperty *prop;			/* ID-properties to provide 'custom' settings */
 } FMod_Python;
 
+
+/* limits modifier data */
+typedef struct FMod_Limits {
+	rctf rect;					/* rect defining the min/max values */
+	int flag;					/* settings for limiting */
+	int pad;
+} FMod_Limits;
+
+/* limiting flags */
+enum {
+	FCM_LIMIT_XMIN		= (1<<0),
+	FCM_LIMIT_XMAX		= (1<<1),
+	FCM_LIMIT_YMIN		= (1<<2),
+	FCM_LIMIT_YMAX		= (1<<3),
+} eFMod_Limit_Flags;
+
 /* Drivers -------------------------------------- */
 
 /* Channel Driver (i.e. Drivers / Expressions) (driver)