NLA SoC: Separating out F-Modifier API

* F-Modifier API is now in its own file in blenkernel
* Renamed and refactored these so that they're no dependent on F-Curves, since all they really used was the fcu->modifiers list
* Added missing license blocks to a few files

1 files changed, 1197 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/fmodifier.c b/source/blender/blenkernel/intern/fmodifier.c
new file mode 100644
index 00000000000..aa5214979d9
--- /dev/null
+++ b/source/blender/blenkernel/intern/fmodifier.c
@@ -0,0 +1,1197 @@
+/**
+ * $Id: fcurve.c 21299 2009-07-02 02:12:37Z aligorith $
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The Original Code is Copyright (C) 2009 Blender Foundation, Joshua Leung
+ * All rights reserved.
+ *
+ * Contributor(s): Joshua Leung (full recode)
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+
+#include <math.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <string.h>
+#include <float.h>
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "MEM_guardedalloc.h"
+
+#include "DNA_anim_types.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_arithb.h"
+#include "BLI_noise.h"
+
+#include "BKE_fcurve.h"
+#include "BKE_curve.h" 
+#include "BKE_global.h"
+#include "BKE_idprop.h"
+#include "BKE_utildefines.h"
+
+#include "RNA_access.h"
+#include "RNA_types.h"
+
+#ifndef DISABLE_PYTHON
+#include "BPY_extern.h" /* for BPY_pydriver_eval() */
+#endif
+
+#define SMALL -1.0e-10
+#define SELECT 1
+
+/* ******************************** F-Modifiers ********************************* */
+
+/* Info ------------------------------- */
+
+/* F-Modifiers are modifiers which operate on F-Curves. However, they can also be defined
+ * on NLA-Strips to affect all of the F-Curves referenced by the NLA-Strip. 
+ */
+
+/* Template --------------------------- */
+
+/* Each modifier defines a set of functions, which will be called at the appropriate
+ * times. In addition to this, each modifier should have a type-info struct, where
+ * its functions are attached for use. 
+ */
+ 
+/* Template for type-info data:
+ *	- make a copy of this when creating new modifiers, and just change the functions
+ *	  pointed to as necessary
+ *	- although the naming of functions doesn't matter, it would help for code
+ *	  readability, to follow the same naming convention as is presented here
+ * 	- any functions that a constraint doesn't need to define, don't define
+ *	  for such cases, just use NULL 
+ *	- these should be defined after all the functions have been defined, so that
+ * 	  forward-definitions/prototypes don't need to be used!
+ *	- keep this copy #if-def'd so that future constraints can get based off this
+ */
+#if 0
+static FModifierTypeInfo FMI_MODNAME = {
+	FMODIFIER_TYPE_MODNAME, /* type */
+	sizeof(FMod_ModName), /* size */
+	FMI_TYPE_SOME_ACTION, /* action type */
+	FMI_REQUIRES_SOME_REQUIREMENT, /* requirements */
+	"Modifier Name", /* name */
+	"FMod_ModName", /* struct name */
+	fcm_modname_free, /* free data */
+	fcm_modname_relink, /* relink data */
+	fcm_modname_copy, /* copy data */
+	fcm_modname_new_data, /* new data */
+	fcm_modname_verify, /* verify */
+	fcm_modname_time, /* evaluate time */
+	fcm_modname_evaluate /* evaluate */
+};
+#endif
+
+/* Generator F-Curve Modifier --------------------------- */
+
+/* Generators available:
+ * 	1) simple polynomial generator:
+ *		- Exanded form - (y = C[0]*(x^(n)) + C[1]*(x^(n-1)) + ... + C[n])  
+ *		- Factorised form - (y = (C[0][0]*x + C[0][1]) * (C[1][0]*x + C[1][1]) * ... * (C[n][0]*x + C[n][1]))
+ */
+
+static void fcm_generator_free (FModifier *fcm)
+{
+	FMod_Generator *data= (FMod_Generator *)fcm->data;
+	
+	/* free polynomial coefficients array */
+	if (data->coefficients)
+		MEM_freeN(data->coefficients);
+}
+
+static void fcm_generator_copy (FModifier *fcm, FModifier *src)
+{
+	FMod_Generator *gen= (FMod_Generator *)fcm->data;
+	FMod_Generator *ogen= (FMod_Generator *)src->data;
+	
+	/* copy coefficients array? */
+	if (ogen->coefficients)
+		gen->coefficients= MEM_dupallocN(ogen->coefficients);
+}
+
+static void fcm_generator_new_data (void *mdata)
+{
+	FMod_Generator *data= (FMod_Generator *)mdata;
+	float *cp;
+	
+	/* set default generator to be linear 0-1 (gradient = 1, y-offset = 0) */
+	data->poly_order= 1;
+	data->arraysize= 2;
+	cp= data->coefficients= MEM_callocN(sizeof(float)*2, "FMod_Generator_Coefs");
+	cp[0] = 0; // y-offset 
+	cp[1] = 1; // gradient
+}
+
+static void fcm_generator_verify (FModifier *fcm)
+{
+	FMod_Generator *data= (FMod_Generator *)fcm->data;
+	
+	/* requirements depend on mode */
+	switch (data->mode) {
+		case FCM_GENERATOR_POLYNOMIAL: /* expanded polynomial expression */
+		{
+			/* arraysize needs to be order+1, so resize if not */
+			if (data->arraysize != (data->poly_order+1)) {
+				float *nc;
+				
+				/* make new coefficients array, and copy over as much data as can fit */
+				nc= MEM_callocN(sizeof(float)*(data->poly_order+1), "FMod_Generator_Coefs");
+				
+				if (data->coefficients) {
+					if (data->arraysize > (data->poly_order+1))
+						memcpy(nc, data->coefficients, sizeof(float)*(data->poly_order+1));
+					else
+						memcpy(nc, data->coefficients, sizeof(float)*data->arraysize);
+						
+					/* free the old data */
+					MEM_freeN(data->coefficients);
+				}	
+				
+				/* set the new data */
+				data->coefficients= nc;
+				data->arraysize= data->poly_order+1;
+			}
+		}
+			break;
+		
+		case FCM_GENERATOR_POLYNOMIAL_FACTORISED: /* expanded polynomial expression */
+		{
+			/* arraysize needs to be 2*order, so resize if not */
+			if (data->arraysize != (data->poly_order * 2)) {
+				float *nc;
+				
+				/* make new coefficients array, and copy over as much data as can fit */
+				nc= MEM_callocN(sizeof(float)*(data->poly_order*2), "FMod_Generator_Coefs");
+				
+				if (data->coefficients) {
+					if (data->arraysize > (data->poly_order * 2))
+						memcpy(nc, data->coefficients, sizeof(float)*(data->poly_order * 2));
+					else
+						memcpy(nc, data->coefficients, sizeof(float)*data->arraysize);
+						
+					/* free the old data */
+					MEM_freeN(data->coefficients);
+				}	
+				
+				/* set the new data */
+				data->coefficients= nc;
+				data->arraysize= data->poly_order * 2;
+			}
+		}
+			break;	
+	}
+}
+
+static void fcm_generator_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
+{
+	FMod_Generator *data= (FMod_Generator *)fcm->data;
+	
+	/* behaviour depends on mode 
+	 * NOTE: the data in its default state is fine too
+	 */
+	switch (data->mode) {
+		case FCM_GENERATOR_POLYNOMIAL: /* expanded polynomial expression */
+		{
+			/* we overwrite cvalue with the sum of the polynomial */
+			float *powers = MEM_callocN(sizeof(float)*data->arraysize, "Poly Powers");
+			float value= 0.0f;
+			unsigned int i;
+			
+			/* for each x^n, precalculate value based on previous one first... this should be 
+			 * faster that calling pow() for each entry
+			 */
+			for (i=0; i < data->arraysize; i++) {
+				/* first entry is x^0 = 1, otherwise, calculate based on previous */
+				if (i)
+					powers[i]= powers[i-1] * evaltime;
+				else
+					powers[0]= 1;
+			}
+			
+			/* for each coefficient, add to value, which we'll write to *cvalue in one go */
+			for (i=0; i < data->arraysize; i++)
+				value += data->coefficients[i] * powers[i];
+			
+			/* only if something changed, write *cvalue in one go */
+			if (data->poly_order) {
+				if (data->flag & FCM_GENERATOR_ADDITIVE)
+					*cvalue += value;
+				else
+					*cvalue= value;
+			}
+				
+			/* cleanup */
+			if (powers) 
+				MEM_freeN(powers);
+		}
+			break;
+			
+		case FCM_GENERATOR_POLYNOMIAL_FACTORISED: /* factorised polynomial */
+		{
+			float value= 1.0f, *cp=NULL;
+			unsigned int i;
+			
+			/* for each coefficient pair, solve for that bracket before accumulating in value by multiplying */
+			for (cp=data->coefficients, i=0; (cp) && (i < data->poly_order); cp+=2, i++) 
+				value *= (cp[0]*evaltime + cp[1]);
+				
+			/* only if something changed, write *cvalue in one go */
+			if (data->poly_order) {
+				if (data->flag & FCM_GENERATOR_ADDITIVE)
+					*cvalue += value;
+				else
+					*cvalue= value;
+			}
+		}
+			break;
+	}
+}
+
+static FModifierTypeInfo FMI_GENERATOR = {
+	FMODIFIER_TYPE_GENERATOR, /* type */
+	sizeof(FMod_Generator), /* size */
+	FMI_TYPE_GENERATE_CURVE, /* action type */
+	FMI_REQUIRES_NOTHING, /* requirements */
+	"Generator", /* name */
+	"FMod_Generator", /* struct name */
+	fcm_generator_free, /* free data */
+	fcm_generator_copy, /* copy data */
+	fcm_generator_new_data, /* new data */
+	fcm_generator_verify, /* verify */
+	NULL, /* evaluate time */
+	fcm_generator_evaluate /* evaluate */
+};
+
+/* Built-In Function Generator F-Curve Modifier --------------------------- */
+
+/* This uses the general equation for equations:
+ * 		y = amplitude * fn(phase_multiplier*x + phase_offset) + y_offset
+ *
+ * where amplitude, phase_multiplier/offset, y_offset are user-defined coefficients,
+ * x is the evaluation 'time', and 'y' is the resultant value
+ *
+ * Functions available are
+ *	sin, cos, tan, sinc (normalised sin), natural log, square root 
+ */
+
+static void fcm_fn_generator_new_data (void *mdata)
+{
+	FMod_FunctionGenerator *data= (FMod_FunctionGenerator *)mdata;
+	
+	/* set amplitude and phase multiplier to 1.0f so that something is generated */
+	data->amplitude= 1.0f;
+	data->phase_multiplier= 1.0f;
+}
+
+/* Unary 'normalised sine' function
+ * 	y = sin(PI + x) / (PI * x),
+ * except for x = 0 when y = 1.
+ */
+static double sinc (double x)
+{
+    if (fabs(x) < 0.0001)
+        return 1.0;
+    else
+        return sin(M_PI * x) / (M_PI * x);
+}
+
+static void fcm_fn_generator_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
+{
+	FMod_FunctionGenerator *data= (FMod_FunctionGenerator *)fcm->data;
+	double arg= data->phase_multiplier*evaltime + data->phase_offset;
+	double (*fn)(double v) = NULL;
+	
+	/* get function pointer to the func to use:
+	 * WARNING: must perform special argument validation hereto guard against crashes  
+	 */
+	switch (data->type)
+	{
+		/* simple ones */			
+		case FCM_GENERATOR_FN_SIN: /* sine wave */
+			fn= sin;
+			break;
+		case FCM_GENERATOR_FN_COS: /* cosine wave */
+			fn= cos;
+			break;
+		case FCM_GENERATOR_FN_SINC: /* normalised sine wave */
+			fn= sinc;
+			break;
+			
+		/* validation required */
+		case FCM_GENERATOR_FN_TAN: /* tangent wave */
+		{
+			/* check that argument is not on one of the discontinuities (i.e. 90deg, 270 deg, etc) */
+			if IS_EQ(fmod((arg - M_PI_2), M_PI), 0.0) {
+				if ((data->flag & FCM_GENERATOR_ADDITIVE) == 0)
+					*cvalue = 0.0f; /* no value possible here */
+			}
+			else
+				fn= tan;
+		}
+			break;
+		case FCM_GENERATOR_FN_LN: /* natural log */
+		{
+			/* check that value is greater than 1? */
+			if (arg > 1.0f) {
+				fn= log;
+			}
+			else {
+				if ((data->flag & FCM_GENERATOR_ADDITIVE) == 0)
+					*cvalue = 0.0f; /* no value possible here */
+			}
+		}
+			break;
+		case FCM_GENERATOR_FN_SQRT: /* square root */
+		{
+			/* no negative numbers */
+			if (arg > 0.0f) {
+				fn= sqrt;
+			}
+			else {
+				if ((data->flag & FCM_GENERATOR_ADDITIVE) == 0)
+					*cvalue = 0.0f; /* no value possible here */
+			}
+		}
+			break;
+		
+		default:
+			printf("Invalid Function-Generator for F-Modifier - %d \n", data->type);
+	}
+	
+	/* execute function callback to set value if appropriate */
+	if (fn) {
+		float value= (float)(data->amplitude*fn(arg) + data->value_offset);
+		
+		if (data->flag & FCM_GENERATOR_ADDITIVE)
+			*cvalue += value;
+		else
+			*cvalue= value;
+	}
+}
+
+static FModifierTypeInfo FMI_FN_GENERATOR = {
+	FMODIFIER_TYPE_FN_GENERATOR, /* type */
+	sizeof(FMod_FunctionGenerator), /* size */
+	FMI_TYPE_GENERATE_CURVE, /* action type */
+	FMI_REQUIRES_NOTHING, /* requirements */
+	"Built-In Function", /* name */
+	"FMod_FunctionGenerator", /* struct name */
+	NULL, /* free data */
+	NULL, /* copy data */
+	fcm_fn_generator_new_data, /* new data */
+	NULL, /* verify */
+	NULL, /* evaluate time */
+	fcm_fn_generator_evaluate /* evaluate */
+};
+
+/* Envelope F-Curve Modifier --------------------------- */
+
+static void fcm_envelope_free (FModifier *fcm)
+{
+	FMod_Envelope *env= (FMod_Envelope *)fcm->data;
+	
+	/* free envelope data array */
+	if (env->data)
+		MEM_freeN(env->data);
+}
+
+static void fcm_envelope_copy (FModifier *fcm, FModifier *src)
+{
+	FMod_Envelope *env= (FMod_Envelope *)fcm->data;
+	FMod_Envelope *oenv= (FMod_Envelope *)src->data;
+	
+	/* copy envelope data array */
+	if (oenv->data)
+		env->data= MEM_dupallocN(oenv->data);
+}
+
+static void fcm_envelope_new_data (void *mdata)
+{
+	FMod_Envelope *env= (FMod_Envelope *)mdata;
+	
+	/* set default min/max ranges */
+	env->min= -1.0f;
+	env->max= 1.0f;
+}
+
+static void fcm_envelope_verify (FModifier *fcm)
+{
+	FMod_Envelope *env= (FMod_Envelope *)fcm->data;
+	
+	/* if the are points, perform bubble-sort on them, as user may have changed the order */
+	if (env->data) {
+		// XXX todo...
+	}
+}
+
+static void fcm_envelope_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
+{
+	FMod_Envelope *env= (FMod_Envelope *)fcm->data;
+	FCM_EnvelopeData *fed, *prevfed, *lastfed;
+	float min=0.0f, max=0.0f, fac=0.0f;
+	int a;
+	
+	/* get pointers */
+	if (env->data == NULL) return;
+	prevfed= env->data;
+	fed= prevfed + 1;
+	lastfed= prevfed + (env->totvert-1);
+	
+	/* get min/max values for envelope at evaluation time (relative to mid-value) */
+	if (prevfed->time >= evaltime) {
+		/* before or on first sample, so just extend value */
+		min= prevfed->min;
+		max= prevfed->max;
+	}
+	else if (lastfed->time <= evaltime) {
+		/* after or on last sample, so just extend value */
+		min= lastfed->min;
+		max= lastfed->max;
+	}
+	else {
+		/* evaltime occurs somewhere between segments */
+		// TODO: implement binary search for this to make it faster?
+		for (a=0; prevfed && fed && (a < env->totvert-1); a++, prevfed=fed, fed++) {  
+			/* evaltime occurs within the interval defined by these two envelope points */
+			if ((prevfed->time <= evaltime) && (fed->time >= evaltime)) {
+				float afac, bfac, diff;
+				
+				diff= fed->time - prevfed->time;
+				afac= (evaltime - prevfed->time) / diff;
+				bfac= (fed->time - evaltime) / diff;
+				
+				min= bfac*prevfed->min + afac*fed->min;
+				max= bfac*prevfed->max + afac*fed->max;
+				
+				break;
+			}
+		}
+	}
+	
+	/* adjust *cvalue 
+	 *	- fac is the ratio of how the current y-value corresponds to the reference range
+	 *	- thus, the new value is found by mapping the old range to the new!
+	 */
+	fac= (*cvalue - (env->midval + env->min)) / (env->max - env->min);
+	*cvalue= min + fac*(max - min); 
+}
+
+static FModifierTypeInfo FMI_ENVELOPE = {
+	FMODIFIER_TYPE_ENVELOPE, /* type */
+	sizeof(FMod_Envelope), /* size */
+	FMI_TYPE_REPLACE_VALUES, /* action type */
+	0, /* requirements */
+	"Envelope", /* name */
+	"FMod_Envelope", /* struct name */
+	fcm_envelope_free, /* free data */
+	fcm_envelope_copy, /* copy data */
+	fcm_envelope_new_data, /* new data */
+	fcm_envelope_verify, /* verify */
+	NULL, /* evaluate time */
+	fcm_envelope_evaluate /* evaluate */
+};
+
+/* Cycles F-Curve Modifier  --------------------------- */
+
+/* This modifier changes evaltime to something that exists within the curve's frame-range, 
+ * then re-evaluates modifier stack up to this point using the new time. This re-entrant behaviour
+ * is very likely to be more time-consuming than the original approach... (which was tighly integrated into 
+ * the calculation code...).
+ *
+ * NOTE: this needs to be at the start of the stack to be of use, as it needs to know the extents of the keyframes/sample-data
+ * Possible TODO - store length of cycle information that can be initialised from the extents of the keyframes/sample-data, and adjusted
+ * 				as appropriate
+ */
+
+/* temp data used during evaluation */
+typedef struct tFCMED_Cycles {
+	float cycyofs;		/* y-offset to apply */
+} tFCMED_Cycles;
+ 
+static void fcm_cycles_new_data (void *mdata)
+{
+	FMod_Cycles *data= (FMod_Cycles *)mdata;
+	
+	/* turn on cycles by default */
+	data->before_mode= data->after_mode= FCM_EXTRAPOLATE_CYCLIC;
+}
+
+static float fcm_cycles_time (FCurve *fcu, FModifier *fcm, float cvalue, float evaltime)
+{
+	FMod_Cycles *data= (FMod_Cycles *)fcm->data;
+	float prevkey[2], lastkey[2], cycyofs=0.0f;
+	short side=0, mode=0;
+	int cycles=0;
+	
+	/* check if modifier is first in stack, otherwise disable ourself... */
+	// FIXME...
+	if (fcm->prev) {
+		fcm->flag |= FMODIFIER_FLAG_DISABLED;
+		return evaltime;
+	}
+	
+	/* calculate new evaltime due to cyclic interpolation */
+	if (fcu && fcu->bezt) {
+		BezTriple *prevbezt= fcu->bezt;
+		BezTriple *lastbezt= prevbezt + fcu->totvert-1;
+		
+		prevkey[0]= prevbezt->vec[1][0];
+		prevkey[1]= prevbezt->vec[1][1];
+		
+		lastkey[0]= lastbezt->vec[1][0];
+		lastkey[1]= lastbezt->vec[1][1];
+	}
+	else if (fcu && fcu->fpt) {
+		FPoint *prevfpt= fcu->fpt;
+		FPoint *lastfpt= prevfpt + fcu->totvert-1;
+		
+		prevkey[0]= prevfpt->vec[0];
+		prevkey[1]= prevfpt->vec[1];
+		
+		lastkey[0]= lastfpt->vec[0];
+		lastkey[1]= lastfpt->vec[1];
+	}
+	else
+		return evaltime;
+		
+	/* check if modifier will do anything
+	 *	1) if in data range, definitely don't do anything
+	 *	2) if before first frame or after last frame, make sure some cycling is in use
+	 */
+	if (evaltime < prevkey[0]) {
+		if (data->before_mode)  {
+			side= -1;
+			mode= data->before_mode;
+			cycles= data->before_cycles;
+		}
+	}
+	else if (evaltime > lastkey[0]) {
+		if (data->after_mode) {
+			side= 1;
+			mode= data->after_mode;
+			cycles= data->after_cycles;
+		}
+	}
+	if ELEM(0, side, mode)
+		return evaltime;
+		
+	/* find relative place within a cycle */
+	{
+		float cycdx=0, cycdy=0, ofs=0;
+		float cycle= 0;
+		
+		/* ofs is start frame of cycle */
+		ofs= prevkey[0];
+		
+		/* calculate period and amplitude (total height) of a cycle */
+		cycdx= lastkey[0] - prevkey[0];
+		cycdy= lastkey[1] - prevkey[1];
+		
+		/* check if cycle is infinitely small, to be point of being impossible to use */
+		if (cycdx == 0)
+			return evaltime;
+			
+		/* calculate the 'number' of the cycle */
+		cycle= ((float)side * (evaltime - ofs) / cycdx);
+		
+		/* check that cyclic is still enabled for the specified time */
+		if (cycles == 0) {
+			/* catch this case so that we don't exit when we have cycles=0
+			 * as this indicates infinite cycles...
+			 */
+		}
+		else if (cycle > (cycles+1)) {
+			/* we are too far away from range to evaluate
+			 * TODO: but we should still hold last value... 
+			 */
+			return evaltime;
+		}
+		
+		/* check if 'cyclic extrapolation', and thus calculate y-offset for this cycle */
+		if (mode == FCM_EXTRAPOLATE_CYCLIC_OFFSET) {
+			cycyofs = (float)floor((evaltime - ofs) / cycdx);
+			cycyofs *= cycdy;
+		}
+		
+		/* calculate where in the cycle we are (overwrite evaltime to reflect this) */
+		if ((mode == FCM_EXTRAPOLATE_MIRROR) && ((int)(cycle) % 2)) {
+			/* when 'mirror' option is used and cycle number is odd, this cycle is played in reverse 
+			 *	- for 'before' extrapolation, we need to flip in a different way, otherwise values past
+			 *	  then end of the curve get referenced (result of fmod will be negative, and with different phase)
+			 */
+			if (side < 0)
+				evaltime= (float)(prevkey[0] - fmod(evaltime-ofs, cycdx));
+			else
+				evaltime= (float)(lastkey[0] - fmod(evaltime-ofs, cycdx));
+		}
+		else {
+			/* the cycle is played normally... */
+			evaltime= (float)(fmod(evaltime-ofs, cycdx) + ofs);
+		}
+		if (evaltime < ofs) evaltime += cycdx;
+	}
+	
+	/* store temp data if needed */
+	if (mode == FCM_EXTRAPOLATE_CYCLIC_OFFSET) {
+		tFCMED_Cycles *edata;
+		
+		/* for now, this is just a float, but we could get more stuff... */
+		fcm->edata= edata= MEM_callocN(sizeof(tFCMED_Cycles), "tFCMED_Cycles");
+		edata->cycyofs= cycyofs;
+	}
+	
+	/* return the new frame to evaluate */
+	return evaltime;
+}
+ 
+static void fcm_cycles_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
+{
+	tFCMED_Cycles *edata= (tFCMED_Cycles *)fcm->edata;
+	
+	/* use temp data */
+	if (edata) {
+		/* add cyclic offset - no need to check for now, otherwise the data wouldn't exist! */
+		*cvalue += edata->cycyofs;
+		
+		/* free temp data */
+		MEM_freeN(edata);
+		fcm->edata= NULL;
+	}
+}
+
+static FModifierTypeInfo FMI_CYCLES = {
+	FMODIFIER_TYPE_CYCLES, /* type */
+	sizeof(FMod_Cycles), /* size */
+	FMI_TYPE_EXTRAPOLATION, /* action type */
+	FMI_REQUIRES_ORIGINAL_DATA, /* requirements */
+	"Cycles", /* name */
+	"FMod_Cycles", /* struct name */
+	NULL, /* free data */
+	NULL, /* copy data */
+	fcm_cycles_new_data, /* new data */
+	NULL /*fcm_cycles_verify*/, /* verify */
+	fcm_cycles_time, /* evaluate time */
+	fcm_cycles_evaluate /* evaluate */
+};
+
+/* Noise F-Curve Modifier  --------------------------- */
+
+static void fcm_noise_new_data (void *mdata)
+{
+	FMod_Noise *data= (FMod_Noise *)mdata;
+	
+	/* defaults */
+	data->size= 1.0f;
+	data->strength= 1.0f;
+	data->phase= 1.0f;
+	data->depth = 0;
+	data->modification = FCM_NOISE_MODIF_REPLACE;
+}
+ 
+static void fcm_noise_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
+{
+	FMod_Noise *data= (FMod_Noise *)fcm->data;
+	float noise;
+	
+	noise = BLI_turbulence(data->size, evaltime, data->phase, 0.f, data->depth);
+	
+	switch (data->modification) {
+		case FCM_NOISE_MODIF_ADD:
+			*cvalue= *cvalue + noise * data->strength;
+			break;
+		case FCM_NOISE_MODIF_SUBTRACT:
+			*cvalue= *cvalue - noise * data->strength;
+			break;
+		case FCM_NOISE_MODIF_MULTIPLY:
+			*cvalue= *cvalue * noise * data->strength;
+			break;
+		case FCM_NOISE_MODIF_REPLACE:
+		default:
+			*cvalue= *cvalue + (noise - 0.5f) * data->strength;
+			break;
+	}
+}
+
+static FModifierTypeInfo FMI_NOISE = {
+	FMODIFIER_TYPE_NOISE, /* type */
+	sizeof(FMod_Noise), /* size */
+	FMI_TYPE_REPLACE_VALUES, /* action type */
+	0, /* requirements */
+	"Noise", /* name */
+	"FMod_Noise", /* struct name */
+	NULL, /* free data */
+	NULL, /* copy data */
+	fcm_noise_new_data, /* new data */
+	NULL /*fcm_noise_verify*/, /* verify */
+	NULL, /* evaluate time */
+	fcm_noise_evaluate /* evaluate */
+};
+
+/* Filter F-Curve Modifier --------------------------- */
+
+#if 0 // XXX not yet implemented 
+static FModifierTypeInfo FMI_FILTER = {
+	FMODIFIER_TYPE_FILTER, /* type */
+	sizeof(FMod_Filter), /* size */
+	FMI_TYPE_REPLACE_VALUES, /* action type */
+	0, /* requirements */
+	"Filter", /* name */
+	"FMod_Filter", /* struct name */
+	NULL, /* free data */
+	NULL, /* copy data */
+	NULL, /* new data */
+	NULL /*fcm_filter_verify*/, /* verify */
+	NULL, /* evlauate time */
+	fcm_filter_evaluate /* evaluate */
+};
+#endif // XXX not yet implemented
+
+
+/* Python F-Curve Modifier --------------------------- */
+
+static void fcm_python_free (FModifier *fcm)
+{
+	FMod_Python *data= (FMod_Python *)fcm->data;
+	
+	/* id-properties */
+	IDP_FreeProperty(data->prop);
+	MEM_freeN(data->prop);
+}
+
+static void fcm_python_new_data (void *mdata) 
+{
+	FMod_Python *data= (FMod_Python *)mdata;
+	
+	/* everything should be set correctly by calloc, except for the prop->type constant.*/
+	data->prop = MEM_callocN(sizeof(IDProperty), "PyFModifierProps");
+	data->prop->type = IDP_GROUP;
+}
+
+static void fcm_python_copy (FModifier *fcm, FModifier *src)
+{
+	FMod_Python *pymod = (FMod_Python *)fcm->data;
+	FMod_Python *opymod = (FMod_Python *)src->data;
+	
+	pymod->prop = IDP_CopyProperty(opymod->prop);
+}
+
+static void fcm_python_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
+{
+#ifndef DISABLE_PYTHON
+	//FMod_Python *data= (FMod_Python *)fcm->data;
+	
+	/* FIXME... need to implement this modifier...
+	 *	It will need it execute a script using the custom properties 
+	 */
+#endif /* DISABLE_PYTHON */
+}
+
+static FModifierTypeInfo FMI_PYTHON = {
+	FMODIFIER_TYPE_PYTHON, /* type */
+	sizeof(FMod_Python), /* size */
+	FMI_TYPE_GENERATE_CURVE, /* action type */
+	FMI_REQUIRES_RUNTIME_CHECK, /* requirements */
+	"Python", /* name */
+	"FMod_Python", /* struct name */
+	fcm_python_free, /* free data */
+	fcm_python_copy, /* copy data */
+	fcm_python_new_data, /* new data */
+	NULL /*fcm_python_verify*/, /* verify */
+	NULL /*fcm_python_time*/, /* evaluate time */
+	fcm_python_evaluate /* evaluate */
+};
+
+
+/* Limits F-Curve Modifier --------------------------- */
+
+static float fcm_limits_time (FCurve *fcu, FModifier *fcm, float cvalue, float evaltime)
+{
+	FMod_Limits *data= (FMod_Limits *)fcm->data;
+	
+	/* check for the time limits */
+	if ((data->flag & FCM_LIMIT_XMIN) && (evaltime < data->rect.xmin))
+		return data->rect.xmin;
+	if ((data->flag & FCM_LIMIT_XMAX) && (evaltime > data->rect.xmax))
+		return data->rect.xmax;
+		
+	/* modifier doesn't change time */
+	return evaltime;
+}
+
+static void fcm_limits_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
+{
+	FMod_Limits *data= (FMod_Limits *)fcm->data;
+	
+	/* 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, /* verify */
+	fcm_limits_time, /* evaluate time */
+	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.
+ */
+
+/* These globals only ever get directly accessed in this file */
+static FModifierTypeInfo *fmodifiersTypeInfo[FMODIFIER_NUM_TYPES];
+static short FMI_INIT= 1; /* when non-zero, the list needs to be updated */
+
+/* This function only gets called when FMI_INIT is non-zero */
+static void fmods_init_typeinfo () 
+{
+	fmodifiersTypeInfo[0]=  NULL; 					/* 'Null' F-Curve Modifier */
+	fmodifiersTypeInfo[1]=  &FMI_GENERATOR; 		/* Generator F-Curve Modifier */
+	fmodifiersTypeInfo[2]=	&FMI_FN_GENERATOR;		/* Built-In Function Generator F-Curve Modifier */
+	fmodifiersTypeInfo[3]=  &FMI_ENVELOPE;			/* Envelope F-Curve Modifier */
+	fmodifiersTypeInfo[4]=  &FMI_CYCLES;			/* Cycles F-Curve Modifier */
+	fmodifiersTypeInfo[5]=  &FMI_NOISE;				/* Apply-Noise F-Curve Modifier */
+	fmodifiersTypeInfo[6]=  NULL/*&FMI_FILTER*/;			/* Filter F-Curve Modifier */  // XXX unimplemented
+	fmodifiersTypeInfo[7]=  &FMI_PYTHON;			/* Custom Python F-Curve Modifier */
+	fmodifiersTypeInfo[8]= 	&FMI_LIMITS;			/* Limits F-Curve Modifier */
+}
+
+/* This function should be used for getting the appropriate type-info when only
+ * a F-Curve modifier type is known
+ */
+FModifierTypeInfo *get_fmodifier_typeinfo (int type)
+{
+	/* initialise the type-info list? */
+	if (FMI_INIT) {
+		fmods_init_typeinfo();
+		FMI_INIT = 0;
+	}
+	
+	/* only return for valid types */
+	if ( (type >= FMODIFIER_TYPE_NULL) && 
+		 (type <= FMODIFIER_NUM_TYPES ) ) 
+	{
+		/* there shouldn't be any segfaults here... */
+		return fmodifiersTypeInfo[type];
+	}
+	else {
+		printf("No valid F-Curve Modifier type-info data available. Type = %i \n", type);
+	}
+	
+	return NULL;
+} 
+ 
+/* This function should always be used to get the appropriate type-info, as it
+ * has checks which prevent segfaults in some weird cases.
+ */
+FModifierTypeInfo *fmodifier_get_typeinfo (FModifier *fcm)
+{
+	/* only return typeinfo for valid modifiers */
+	if (fcm)
+		return get_fmodifier_typeinfo(fcm->type);
+	else
+		return NULL;
+}
+
+/* API --------------------------- */
+
+/* Add a new F-Curve Modifier to the given F-Curve of a certain type */
+FModifier *add_fmodifier (ListBase *modifiers, int type)
+{
+	FModifierTypeInfo *fmi= get_fmodifier_typeinfo(type);
+	FModifier *fcm;
+	
+	/* sanity checks */
+	if ELEM(NULL, modifiers, fmi)
+		return NULL;
+	
+	/* special checks for whether modifier can be added */
+	if ((modifiers->first) && (type == FMODIFIER_TYPE_CYCLES)) {
+		/* cycles modifier must be first in stack, so for now, don't add if it can't be */
+		// TODO: perhaps there is some better way, but for now, 
+		printf("Error: Cannot add 'Cycles' modifier to F-Curve, as 'Cycles' modifier can only be first in stack. \n");
+		return NULL;
+	}
+	
+	/* add modifier itself */
+	fcm= MEM_callocN(sizeof(FModifier), "F-Curve Modifier");
+	fcm->type = type;
+	fcm->flag = FMODIFIER_FLAG_EXPANDED;
+	BLI_addtail(modifiers, fcm);
+	
+	/* add modifier's data */
+	fcm->data= MEM_callocN(fmi->size, fmi->structName);
+		
+	/* init custom settings if necessary */
+	if (fmi->new_data)	
+		fmi->new_data(fcm->data);
+		
+	/* return modifier for further editing */
+	return fcm;
+}
+
+/* Duplicate all of the F-Modifiers in the Modifier stacks */
+void copy_fmodifiers (ListBase *dst, ListBase *src)
+{
+	FModifier *fcm, *srcfcm;
+	
+	if ELEM(NULL, dst, src)
+		return;
+	
+	dst->first= dst->last= NULL;
+	BLI_duplicatelist(dst, src);
+	
+	for (fcm=dst->first, srcfcm=src->first; fcm && srcfcm; srcfcm=srcfcm->next, fcm=fcm->next) {
+		FModifierTypeInfo *fmi= fmodifier_get_typeinfo(fcm);
+		
+		/* make a new copy of the F-Modifier's data */
+		fcm->data = MEM_dupallocN(fcm->data);
+		
+		/* only do specific constraints if required */
+		if (fmi && fmi->copy_data)
+			fmi->copy_data(fcm, srcfcm);
+	}
+}
+
+/* Remove and free the given F-Modifier from the given stack  */
+void remove_fmodifier (ListBase *modifiers, FModifier *fcm)
+{
+	FModifierTypeInfo *fmi= fmodifier_get_typeinfo(fcm);
+	
+	/* sanity check */
+	if (fcm == NULL)
+		return;
+	
+	/* free modifier's special data (stored inside fcm->data) */
+	if (fcm->data) {
+		if (fmi && fmi->free_data)
+			fmi->free_data(fcm);
+			
+		/* free modifier's data (fcm->data) */
+		MEM_freeN(fcm->data);
+	}
+	
+	/* remove modifier from stack */
+	if (modifiers)
+		BLI_freelinkN(modifiers, fcm);
+	else {
+		// XXX this case can probably be removed some day, as it shouldn't happen...
+		printf("remove_fmodifier() - no modifier stack given \n");
+		MEM_freeN(fcm);
+	}
+}
+
+/* Remove all of a given F-Curve's modifiers */
+void free_fmodifiers (ListBase *modifiers)
+{
+	FModifier *fcm, *fmn;
+	
+	/* sanity check */
+	if (modifiers == NULL)
+		return;
+	
+	/* free each modifier in order - modifier is unlinked from list and freed */
+	for (fcm= modifiers->first; fcm; fcm= fmn) {
+		fmn= fcm->next;
+		remove_fmodifier(modifiers, fcm);
+	}
+}
+
+/* Find the active F-Modifier */
+FModifier *find_active_fmodifier (ListBase *modifiers)
+{
+	FModifier *fcm;
+	
+	/* sanity checks */
+	if ELEM(NULL, modifiers, modifiers->first)
+		return NULL;
+	
+	/* loop over modifiers until 'active' one is found */
+	for (fcm= modifiers->first; fcm; fcm= fcm->next) {
+		if (fcm->flag & FMODIFIER_FLAG_ACTIVE)
+			return fcm;
+	}
+	
+	/* no modifier is active */
+	return NULL;
+}
+
+/* Set the active F-Modifier */
+void set_active_fmodifier (ListBase *modifiers, FModifier *fcm)
+{
+	FModifier *fm;
+	
+	/* sanity checks */
+	if ELEM(NULL, modifiers, modifiers->first)
+		return;
+	
+	/* deactivate all, and set current one active */
+	for (fm= modifiers->first; fm; fm= fm->next)
+		fm->flag &= ~FMODIFIER_FLAG_ACTIVE;
+	
+	/* make given modifier active */
+	if (fcm)
+		fcm->flag |= FMODIFIER_FLAG_ACTIVE;
+}
+
+/* Do we have any modifiers which match certain criteria 
+ *	- mtype - type of modifier (if 0, doesn't matter)
+ *	- acttype - type of action to perform (if -1, doesn't matter)
+ */
+short list_has_suitable_fmodifier (ListBase *modifiers, int mtype, short acttype)
+{
+	FModifier *fcm;
+	
+	/* if there are no specific filtering criteria, just skip */
+	if ((mtype == 0) && (acttype == 0))
+		return (modifiers && modifiers->first);
+		
+	/* sanity checks */
+	if ELEM(NULL, modifiers, modifiers->first)
+		return 0;
+		
+	/* find the first mdifier fitting these criteria */
+	for (fcm= modifiers->first; fcm; fcm= fcm->next) {
+		FModifierTypeInfo *fmi= fmodifier_get_typeinfo(fcm);
+		short mOk=1, aOk=1; /* by default 1, so that when only one test, won't fail */
+		
+		/* check if applicable ones are fullfilled */
+		if (mtype)
+			mOk= (fcm->type == mtype);
+		if (acttype > -1)
+			aOk= (fmi->acttype == acttype);
+			
+		/* if both are ok, we've found a hit */
+		if (mOk && aOk)
+			return 1;
+	}
+	
+	/* no matches */
+	return 0;
+}  
+
+/* Evaluation API --------------------------- */
+
+/* evaluate time modifications imposed by some F-Curve Modifiers
+ *	- this step acts as an optimisation to prevent the F-Curve stack being evaluated 
+ *	  several times by modifiers requesting the time be modified, as the final result
+ *	  would have required using the modified time
+ *	- modifiers only ever recieve the unmodified time, as subsequent modifiers should be
+ *	  working on the 'global' result of the modified curve, not some localised segment,
+ *	  so nevaltime gets set to whatever the last time-modifying modifier likes...
+ *	- we start from the end of the stack, as only the last one matters for now
+ */
+float evaluate_time_fmodifiers (ListBase *modifiers, FCurve *fcu, float cvalue, float evaltime)
+{
+	FModifier *fcm;
+	float m_evaltime= evaltime;
+	
+	/* sanity checks */
+	if ELEM(NULL, modifiers, modifiers->last)
+		return evaltime;
+		
+	/* find the first modifier from end of stack that modifies time, and calculate the time the modifier
+	 * would calculate time at
+	 */
+	for (fcm= modifiers->last; fcm; fcm= fcm->prev) {
+		FModifierTypeInfo *fmi= fmodifier_get_typeinfo(fcm);
+		
+		/* only evaluate if there's a callback for this */
+		// TODO: implement the 'influence' control feature...
+		if (fmi && fmi->evaluate_modifier_time) {
+			if ((fcm->flag & (FMODIFIER_FLAG_DISABLED|FMODIFIER_FLAG_MUTED)) == 0)
+				m_evaltime= fmi->evaluate_modifier_time(fcu, fcm, cvalue, evaltime);
+			break;
+		}
+	}
+	
+	/* return the modified evaltime */
+	return m_evaltime;
+}
+
+/* Evalautes the given set of F-Curve Modifiers using the given data
+ * Should only be called after evaluate_time_fmodifiers() has been called...
+ */
+void evaluate_value_fmodifiers (ListBase *modifiers, FCurve *fcu, float *cvalue, float evaltime)
+{
+	FModifier *fcm;
+	
+	/* sanity checks */
+	if ELEM(NULL, modifiers, modifiers->first)
+		return;
+	
+	/* evaluate modifiers */
+	for (fcm= modifiers->first; fcm; fcm= fcm->next) {
+		FModifierTypeInfo *fmi= fmodifier_get_typeinfo(fcm);
+		
+		/* only evaluate if there's a callback for this */
+		// TODO: implement the 'influence' control feature...
+		if (fmi && fmi->evaluate_modifier) {
+			if ((fcm->flag & (FMODIFIER_FLAG_DISABLED|FMODIFIER_FLAG_MUTED)) == 0)
+				fmi->evaluate_modifier(fcu, fcm, cvalue, evaltime);
+		}
+	}
+} 
+
+/* ---------- */
+
+/* Bake modifiers for given F-Curve to curve sample data, in the frame range defined
+ * by start and end (inclusive).
+ */
+void fcurve_bake_modifiers (FCurve *fcu, int start, int end)
+{
+	ChannelDriver *driver;
+	
+	/* sanity checks */
+	// TODO: make these tests report errors using reports not printf's
+	if ELEM(NULL, fcu, fcu->modifiers.first) {
+		printf("Error: No F-Curve with F-Curve Modifiers to Bake\n");
+		return;
+	}
+	
+	/* temporarily, disable driver while we sample, so that they don't influence the outcome */
+	driver= fcu->driver;
+	fcu->driver= NULL;
+	
+	/* bake the modifiers, by sampling the curve at each frame */
+	fcurve_store_samples(fcu, NULL, start, end, fcurve_samplingcb_evalcurve);
+	
+	/* free the modifiers now */
+	free_fmodifiers(&fcu->modifiers);
+	
+	/* restore driver */
+	fcu->driver= driver;
+}