NLA SoC: Separated 'Built-In Function Generator' FModifier into a separate FModifier

Started cleaning up FModifiers in preparation for allowing them to be used on NLA Strips. 

This commit separates the 'Built-in Function' mode for the Generator modifier out into its own modifier, since it was being quite frequently used (and the RNA wrapping for this used to be quite hackish). 

BACKWARDS COMPATABILITY WARNING:
Old files with FModifiers saved (i.e. old 2.5 files, but not any others) will not load correctly as a result of these changes (the wrong modifiers will be shown). I've decided that there are not likely to be many files affected by this yet, but doing this will result in a much nicer modifiers-define list in the long run.

6 files changed, 231 insertions, 312 deletions

diff --git a/source/blender/blenkernel/intern/fcurve.c b/source/blender/blenkernel/intern/fcurve.c
index 27ca6332cdc..e52c63d1b21 100644
--- a/source/blender/blenkernel/intern/fcurve.c
+++ b/source/blender/blenkernel/intern/fcurve.c
@@ -1,5 +1,5 @@
 /**
- * $Id: fcurve.c 21023 2009-06-20 04:02:49Z aligorith $
+ * $Id$
  *
  * ***** BEGIN GPL LICENSE BLOCK *****
  *
@@ -1314,11 +1314,6 @@ static FModifierTypeInfo FMI_MODNAME = {
  * 	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]))
- *	2) simple builin 'functions':
- *		of the form (y = C[0] * fn( C[1]*x + C[2] ) + C[3])
- * 	   where fn() can be any one of:
- *		sin, cos, tan, ln, sqrt
- *	3) expression...
  */
 
 static void fcm_generator_free (FModifier *fcm)
@@ -1409,44 +1404,10 @@ static void fcm_generator_verify (FModifier *fcm)
 				data->arraysize= data->poly_order * 2;
 			}
 		}
-			break;
-			
-		case FCM_GENERATOR_FUNCTION: /* builtin function */
-		{
-			/* arraysize needs to be 4*/
-			if (data->arraysize != 4) {
-				float *nc;
-				
-				/* free the old data */
-				if (data->coefficients)
-					MEM_freeN(data->coefficients);
-				
-				/* make new coefficients array, and init using default values */
-				nc= data->coefficients= MEM_callocN(sizeof(float)*4, "FMod_Generator_Coefs");
-				data->arraysize= 4;
-				
-				nc[0]= 1.0f;
-				nc[1]= 1.0f;
-				nc[2]= 0.0f;
-				nc[3]= 0.0f;
-			}
-		}
 			break;	
 	}
 }
 
-/* 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_generator_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue, float evaltime)
 {
 	FMod_Generator *data= (FMod_Generator *)fcm->data;
@@ -1509,86 +1470,6 @@ static void fcm_generator_evaluate (FCurve *fcu, FModifier *fcm, float *cvalue,
 			}
 		}
 			break;
-			
-		case FCM_GENERATOR_FUNCTION: /* builtin function */
-		{
-			double arg= data->coefficients[1]*evaltime + data->coefficients[2];
-			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->func_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->func_type);
-			}
-			
-			/* execute function callback to set value if appropriate */
-			if (fn) {
-				float value= (float)(data->coefficients[0]*fn(arg) + data->coefficients[3]);
-				
-				if (data->flag & FCM_GENERATOR_ADDITIVE)
-					*cvalue += value;
-				else
-					*cvalue= value;
-			}
-		}
-			break;
-
-#ifndef DISABLE_PYTHON
-		case FCM_GENERATOR_EXPRESSION: /* py-expression */
-			// TODO...
-			break;
-#endif /* DISABLE_PYTHON */
 	}
 }
 
@@ -1607,6 +1488,128 @@ static FModifierTypeInfo FMI_GENERATOR = {
 	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)
@@ -2081,12 +2084,13 @@ static void fmods_init_typeinfo ()
 {
 	fmodifiersTypeInfo[0]=  NULL; 					/* 'Null' F-Curve Modifier */
 	fmodifiersTypeInfo[1]=  &FMI_GENERATOR; 		/* Generator F-Curve Modifier */
-	fmodifiersTypeInfo[2]=  &FMI_ENVELOPE;			/* Envelope F-Curve Modifier */
-	fmodifiersTypeInfo[3]=  &FMI_CYCLES;			/* Cycles F-Curve Modifier */
-	fmodifiersTypeInfo[4]=  &FMI_NOISE;				/* Apply-Noise F-Curve Modifier */
-	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 */
+	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
diff --git a/source/blender/editors/space_graph/graph_buttons.c b/source/blender/editors/space_graph/graph_buttons.c
index f2dcd297866..e68ee53521d 100644
--- a/source/blender/editors/space_graph/graph_buttons.c
+++ b/source/blender/editors/space_graph/graph_buttons.c
@@ -404,8 +404,7 @@ static void delete_fmodifier_cb (bContext *C, void *fcu_v, void *fcm_v)
 static void draw_modifier__generator(uiBlock *block, FCurve *fcu, FModifier *fcm, int *yco, short *height, short width, short active, int rb_col)
 {
 	FMod_Generator *data= (FMod_Generator *)fcm->data;
-	char gen_mode[]="Generator Type%t|Expanded Polynomial%x0|Factorised Polynomial%x1|Built-In Function%x2|Expression%x3";
-	char fn_type[]="Built-In Function%t|Sin%x0|Cos%x1|Tan%x2|Square Root%x3|Natural Log%x4|Normalised Sin%x5";
+	char gen_mode[]="Generator Type%t|Expanded Polynomial%x0|Factorised Polynomial%x1";
 	int cy= *yco - 30;
 	uiBut *but;
 	
@@ -418,22 +417,16 @@ static void draw_modifier__generator(uiBlock *block, FCurve *fcu, FModifier *fcm
 		case FCM_GENERATOR_POLYNOMIAL_FACTORISED: /* factorised polynomial */
 			(*height) += 20 * data->poly_order + 15;
 			break;
-		case FCM_GENERATOR_FUNCTION: /* builtin function */
-			(*height) += 55; // xxx
-			break;
-		case FCM_GENERATOR_EXPRESSION: /* py-expression */
-			// xxx nothing to draw 
-			break;
 	}
 	
 	/* basic settings (backdrop + mode selector + some padding) */
 	DRAW_BACKDROP((*height));
 	uiBlockBeginAlign(block);
-		but= uiDefButS(block, MENU, B_FMODIFIER_REDRAW, gen_mode, 10,cy,width-30,19, &data->mode, 0, 0, 0, 0, "Selects type of generator algorithm.");
+		but= uiDefButI(block, MENU, B_FMODIFIER_REDRAW, gen_mode, 10,cy,width-30,19, &data->mode, 0, 0, 0, 0, "Selects type of generator algorithm.");
 		uiButSetFunc(but, validate_fmodifier_cb, fcu, fcm);
 		cy -= 20;
 		
-		uiDefButBitS(block, TOG, FCM_GENERATOR_ADDITIVE, B_FMODIFIER_REDRAW, "Additive", 10,cy,width-30,19, &data->flag, 0, 0, 0, 0, "Values generated by this modifier are applied on top of the existing values instead of overwriting them");
+		uiDefButBitI(block, TOG, FCM_GENERATOR_ADDITIVE, B_FMODIFIER_REDRAW, "Additive", 10,cy,width-30,19, &data->flag, 0, 0, 0, 0, "Values generated by this modifier are applied on top of the existing values instead of overwriting them");
 		cy -= 35;
 	uiBlockEndAlign(block);
 	
@@ -446,7 +439,7 @@ static void draw_modifier__generator(uiBlock *block, FCurve *fcu, FModifier *fcm
 			unsigned int i;
 			
 			/* draw polynomial order selector */
-			but= uiDefButS(block, NUM, B_FMODIFIER_REDRAW, "Poly Order: ", 10,cy,width-30,19, &data->poly_order, 1, 100, 0, 0, "'Order' of the Polynomial - for a polynomial with n terms, 'order' is n-1");
+			but= uiDefButI(block, NUM, B_FMODIFIER_REDRAW, "Poly Order: ", 10,cy,width-30,19, &data->poly_order, 1, 100, 0, 0, "'Order' of the Polynomial - for a polynomial with n terms, 'order' is n-1");
 			uiButSetFunc(but, validate_fmodifier_cb, fcu, fcm);
 			cy -= 35;
 			
@@ -481,7 +474,7 @@ static void draw_modifier__generator(uiBlock *block, FCurve *fcu, FModifier *fcm
 			unsigned int i;
 			
 			/* draw polynomial order selector */
-			but= uiDefButS(block, NUM, B_FMODIFIER_REDRAW, "Poly Order: ", 10,cy,width-30,19, &data->poly_order, 1, 100, 0, 0, "'Order' of the Polynomial - for a polynomial with n terms, 'order' is n-1");
+			but= uiDefButI(block, NUM, B_FMODIFIER_REDRAW, "Poly Order: ", 10,cy,width-30,19, &data->poly_order, 1, 100, 0, 0, "'Order' of the Polynomial - for a polynomial with n terms, 'order' is n-1");
 			uiButSetFunc(but, validate_fmodifier_cb, fcu, fcm);
 			cy -= 35;
 			
@@ -510,82 +503,42 @@ static void draw_modifier__generator(uiBlock *block, FCurve *fcu, FModifier *fcm
 			}
 		}
 			break;
-		
-		case FCM_GENERATOR_FUNCTION: /* built-in function */
-		{
-			float *cp= data->coefficients;
-			
-			/* draw function selector */
-			but= uiDefButS(block, MENU, B_FMODIFIER_REDRAW, fn_type, 10,cy,width-30,19, &data->func_type, 0, 0, 0, 0, "Built-In Function to use");
-			uiButSetFunc(but, validate_fmodifier_cb, fcu, fcm);
-			cy -= 35;
-			
-			/* draw controls for equation of coefficients */
-			/* row 1 */
-			{
-				uiDefBut(block, LABEL, 1, "y = ", 0, cy, 50, 20, NULL, 0.0, 0.0, 0, 0, "");
-				
-				uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "", 50, cy, 150, 20, cp+3, -UI_FLT_MAX, UI_FLT_MAX, 10, 3, "Coefficient (D) for function");
-				uiDefBut(block, LABEL, 1, "+", 200, cy, 30, 20, NULL, 0.0, 0.0, 0, 0, "");
-				cy -= 20;
-			}
-			
-			/* row 2 */
-			{
-				char func_name[32];
-				
-				/* coefficient outside bracket */
-				uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "", 5, cy, 80, 20, cp, -UI_FLT_MAX, UI_FLT_MAX, 10, 3, "Coefficient (A) for function");
-				
-				/* opening bracket */
-				switch (data->func_type)
-				{		
-					case FCM_GENERATOR_FN_SIN: /* sine wave */
-						sprintf(func_name, "sin(");
-						break;
-					case FCM_GENERATOR_FN_COS: /* cosine wave */
-						sprintf(func_name, "cos(");
-						break;
-					case FCM_GENERATOR_FN_TAN: /* tangent wave */
-						sprintf(func_name, "tan(");
-						break;
-					case FCM_GENERATOR_FN_LN: /* natural log */
-						sprintf(func_name, "ln(");
-						break;
-					case FCM_GENERATOR_FN_SQRT: /* square root */
-						sprintf(func_name, "sqrt(");
-						break;
-					case FCM_GENERATOR_FN_SINC: /* normalised sine wave */
-						sprintf(func_name, "sinc(");
-						break;
-					default: /* unknown */
-						sprintf(func_name, "<fn?>(");
-						break;
-				}
-				uiDefBut(block, LABEL, 1, func_name, 85, cy, 40, 20, NULL, 0.0, 0.0, 0, 0, "");
-				
-				/* coefficients inside bracket */
-				uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "", 120, cy, 75, 20, cp+1, -UI_FLT_MAX, UI_FLT_MAX, 10, 3, "Coefficient (B) of x");
-				
-				uiDefBut(block, LABEL, 1, "x+", 195, cy, 30, 20, NULL, 0.0, 0.0, 0, 0, "");
-				
-				uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "", 225, cy, 80, 20, cp+2, -UI_FLT_MAX, UI_FLT_MAX, 10, 3, "Coefficient (C) of function");
-				
-				/* closing bracket */
-					uiDefBut(block, LABEL, 1, ")", 300, cy, 30, 20, NULL, 0.0, 0.0, 0, 0, "");
-				cy -= 20;
-			}
-		}
-			break;
-		
-		case FCM_GENERATOR_EXPRESSION: /* py-expression */
-			// TODO...
-			break;
 	}
 }
 
 /* --------------- */
 
+/* draw settings for noise modifier */
+static void draw_modifier__fn_generator(uiBlock *block, FCurve *fcu, FModifier *fcm, int *yco, short *height, short width, short active, int rb_col)
+{
+	FMod_FunctionGenerator *data= (FMod_FunctionGenerator *)fcm->data;
+	int cy= (*yco - 30), cy1= (*yco - 50), cy2= (*yco - 70);
+	char fn_type[]="Built-In Function%t|Sin%x0|Cos%x1|Tan%x2|Square Root%x3|Natural Log%x4|Normalised Sin%x5";
+	
+	/* set the height */
+	(*height) = 80;
+	
+	/* basic settings (backdrop + some padding) */
+	DRAW_BACKDROP((*height));
+	
+	uiDefButI(block, MENU, B_FMODIFIER_REDRAW, fn_type,
+			  3, cy, 300, 20, &data->type, 0, 0, 0, 0, "Type of function used to generate values");
+	
+	
+	uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "Amplitude:", 
+			  3, cy1, 150, 20, &data->amplitude, 0.000001, 10000.0, 0.01, 3, "Scale factor determining the maximum/minimum values.");
+	uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "Value Offset:", 
+			  3, cy2, 150, 20, &data->value_offset, 0.0, 10000.0, 0.01, 3, "Constant factor to offset values by.");
+	
+	uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "Phase Multiplier:", 
+			  155, cy1, 150, 20, &data->phase_multiplier, 0.0, 100000.0, 0.1, 3, "Scale factor determining the 'speed' of the function.");
+	uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "Phase Offset:", 
+			  155, cy2, 150, 20, &data->phase_offset, 0.0, 100000.0, 0.1, 3, "Constant factor to offset time by for function.");
+
+}
+
+/* --------------- */
+
 /* draw settings for cycles modifier */
 static void draw_modifier__cycles(uiBlock *block, FCurve *fcu, FModifier *fcm, int *yco, short *height, short width, short active, int rb_col)
 {
@@ -621,7 +574,7 @@ static void draw_modifier__noise(uiBlock *block, FCurve *fcu, FModifier *fcm, in
 {
 	FMod_Noise *data= (FMod_Noise *)fcm->data;
 	int cy= (*yco - 30), cy1= (*yco - 50), cy2= (*yco - 70);
-	char cyc_mode[]="Modification %t|Replace %x0|Add %x1|Subtract %x2|Multiply %x3";
+	char blend_mode[]="Modification %t|Replace %x0|Add %x1|Subtract %x2|Multiply %x3";
 	
 	/* set the height */
 	(*height) = 80;
@@ -629,8 +582,8 @@ static void draw_modifier__noise(uiBlock *block, FCurve *fcu, FModifier *fcm, in
 	/* basic settings (backdrop + some padding) */
 	DRAW_BACKDROP((*height));
 	
-	uiDefButS(block, MENU, B_FMODIFIER_REDRAW, cyc_mode,
-			  3, cy, 150, 20, &data->modification, 0, 0, 0, 0, "Method of modifying the existing F-Curve use before first keyframe");
+	uiDefButS(block, MENU, B_FMODIFIER_REDRAW, blend_mode,
+			  3, cy, 150, 20, &data->modification, 0, 0, 0, 0, "Method of combining the results of this modifier and other modifiers.");
 	
 	uiDefButF(block, NUM, B_FMODIFIER_REDRAW, "Size:", 
 			  3, cy1, 150, 20, &data->size, 0.000001, 10000.0, 0.01, 3, "");
@@ -946,6 +899,10 @@ static void graph_panel_modifier_draw(uiBlock *block, FCurve *fcu, FModifier *fc
 				draw_modifier__generator(block, fcu, fcm, yco, &height, width, active, rb_col);
 				break;
 				
+			case FMODIFIER_TYPE_FN_GENERATOR: /* Built-In Function Generator */
+				draw_modifier__fn_generator(block, fcu, fcm, yco, &height, width, active, rb_col);
+				break;
+				
 			case FMODIFIER_TYPE_CYCLES: /* Cycles */
 				draw_modifier__cycles(block, fcu, fcm, yco, &height, width, active, rb_col);
 				break;
diff --git a/source/blender/editors/space_graph/graph_intern.h b/source/blender/editors/space_graph/graph_intern.h
index fd7fe7cc6c9..86e5451122d 100644
--- a/source/blender/editors/space_graph/graph_intern.h
+++ b/source/blender/editors/space_graph/graph_intern.h
@@ -32,6 +32,8 @@ struct bContext;
 struct wmWindowManager;
 struct bAnimContext;
 struct bAnimListElem;
+struct FCurve;
+struct FModifier;
 struct SpaceIpo;
 struct ScrArea;
 struct ARegion;
diff --git a/source/blender/makesdna/DNA_anim_types.h b/source/blender/makesdna/DNA_anim_types.h
index 2b089530236..ad3edde6552 100644
--- a/source/blender/makesdna/DNA_anim_types.h
+++ b/source/blender/makesdna/DNA_anim_types.h
@@ -1,5 +1,5 @@
 /**
- * $Id: DNA_anim_types.h 21023 2009-06-20 04:02:49Z aligorith $
+ * $Id$
  *
  * ***** BEGIN GPL LICENSE BLOCK *****
  *
@@ -66,6 +66,7 @@ typedef struct FModifier {
 enum {
 	FMODIFIER_TYPE_NULL = 0,
 	FMODIFIER_TYPE_GENERATOR,
+	FMODIFIER_TYPE_FN_GENERATOR,
 	FMODIFIER_TYPE_ENVELOPE,
 	FMODIFIER_TYPE_CYCLES,
 	FMODIFIER_TYPE_NOISE,		/* unimplemented - generate variations using some basic noise generator... */
@@ -91,39 +92,55 @@ enum {
 
 /* --- */
 
-/* generator modifier data */
+/* Generator modifier data */
 typedef struct FMod_Generator {
-		/* generator based on PyExpression */
-	char expression[256];		/* python expression to use as generator */
-	
 		/* general generator information */
 	float *coefficients;		/* coefficients array */
 	unsigned int arraysize;		/* size of the coefficients array */
 	
-	short poly_order;			/* order of polynomial generated (i.e. 1 for linear, 2 for quadratic) */
-	short func_type;			/* builtin math function eFMod_Generator_Functions */
-	
-	int pad;
+	int poly_order;				/* order of polynomial generated (i.e. 1 for linear, 2 for quadratic) */
+	int mode;					/* which 'generator' to use eFMod_Generator_Modes */
 	
 		/* settings */
-	short flag;					/* settings */
-	short mode;					/* which 'generator' to use eFMod_Generator_Modes */
+	int flag;					/* settings */
 } FMod_Generator;
 
 /* generator modes */
 enum {
 	FCM_GENERATOR_POLYNOMIAL	= 0,
 	FCM_GENERATOR_POLYNOMIAL_FACTORISED,
-	FCM_GENERATOR_FUNCTION,
-	FCM_GENERATOR_EXPRESSION,
 } eFMod_Generator_Modes;
 
-/* generator flags */
+
+/* generator flags 
+ *	- shared by Generator and Function Generator
+ */
 enum {
 		/* generator works in conjunction with other modifiers (i.e. doesn't replace those before it) */
 	FCM_GENERATOR_ADDITIVE	= (1<<0),
 } eFMod_Generator_Flags;
 
+
+/* 'Built-In Function' Generator modifier data
+ * 
+ * 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
+ */
+typedef struct FMod_FunctionGenerator {
+		/* coefficients for general equation (as above) */
+	float amplitude;
+	float phase_multiplier;
+	float phase_offset;
+	float value_offset;
+	
+		/* flags */
+	int type;				/* eFMod_Generator_Functions */
+	int flag;				/* eFMod_Generator_flags */
+} FMod_FunctionGenerator;
+
 /* 'function' generator types */
 enum {
 	FCM_GENERATOR_FN_SIN	= 0,
diff --git a/source/blender/makesrna/RNA_access.h b/source/blender/makesrna/RNA_access.h
index dda0d57f8ad..cf74a863401 100644
--- a/source/blender/makesrna/RNA_access.h
+++ b/source/blender/makesrna/RNA_access.h
@@ -177,8 +177,8 @@ extern StructRNA RNA_FCurve;
 extern StructRNA RNA_FModifier;
 extern StructRNA RNA_FModifierCycles;
 extern StructRNA RNA_FModifierEnvelope;
+extern StructRNA RNA_FModifierFunctionGenerator;
 extern StructRNA RNA_FModifierGenerator;
-extern StructRNA RNA_FModifierGenerator_Function;
 extern StructRNA RNA_FModifierGenerator_PolyExpanded;
 extern StructRNA RNA_FModifierLimits;
 extern StructRNA RNA_FModifierNoise;
diff --git a/source/blender/makesrna/intern/rna_fcurve.c b/source/blender/makesrna/intern/rna_fcurve.c
index a1cd95c9d90..4a83b80a6cf 100644
--- a/source/blender/makesrna/intern/rna_fcurve.c
+++ b/source/blender/makesrna/intern/rna_fcurve.c
@@ -37,6 +37,7 @@
 EnumPropertyItem fmodifier_type_items[] = {
 	{FMODIFIER_TYPE_NULL, "NULL", 0, "Invalid", ""},
 	{FMODIFIER_TYPE_GENERATOR, "GENERATOR", 0, "Generator", ""},
+	{FMODIFIER_TYPE_FN_GENERATOR, "FNGENERATOR", 0, "Built-In Function", ""},
 	{FMODIFIER_TYPE_ENVELOPE, "ENVELOPE", 0, "Envelope", ""},
 	{FMODIFIER_TYPE_CYCLES, "CYCLES", 0, "Cycles", ""},
 	{FMODIFIER_TYPE_NOISE, "NOISE", 0, "Noise", ""},
@@ -47,62 +48,6 @@ EnumPropertyItem fmodifier_type_items[] = {
 
 #ifdef RNA_RUNTIME
 
-float FModGenFunc_amplitude_get(PointerRNA *ptr)
-{
-	FModifier *fcm = (FModifier *)(ptr->data);
-	FMod_Generator *data= (FMod_Generator*)(fcm->data);
-	return (data->coefficients) ? (float)data->coefficients[0] : 1.0f;
-}
-
-void FModGenFunc_amplitude_set(PointerRNA *ptr, float value)
-{
-	FModifier *fcm = (FModifier *)(ptr->data);
-	FMod_Generator *data= (FMod_Generator*)(fcm->data);
-	if (data->coefficients) data->coefficients[0]= value;
-}
-
-float FModGenFunc_pre_multiplier_get(PointerRNA *ptr)
-{
-	FModifier *fcm = (FModifier *)(ptr->data);
-	FMod_Generator *data= (FMod_Generator*)(fcm->data);
-	return (data->coefficients) ? (float)data->coefficients[1] : 1.0f;
-}
-
-void FModGenFunc_pre_multiplier_set(PointerRNA *ptr, float value)
-{
-	FModifier *fcm = (FModifier *)(ptr->data);
-	FMod_Generator *data= (FMod_Generator*)(fcm->data);
-	if (data->coefficients) data->coefficients[1]= value;
-}
-
-float FModGenFunc_x_offset_get(PointerRNA *ptr)
-{
-	FModifier *fcm = (FModifier *)(ptr->data);
-	FMod_Generator *data= (FMod_Generator*)(fcm->data);
-	return (data->coefficients) ? (float)data->coefficients[2] : 0.0f;
-}
-
-void FModGenFunc_x_offset_set(PointerRNA *ptr, float value)
-{
-	FModifier *fcm = (FModifier *)(ptr->data);
-	FMod_Generator *data= (FMod_Generator*)(fcm->data);
-	if (data->coefficients) data->coefficients[2]= value;
-}
-
-float FModGenFunc_y_offset_get(PointerRNA *ptr)
-{
-	FModifier *fcm = (FModifier *)(ptr->data);
-	FMod_Generator *data= (FMod_Generator*)(fcm->data);
-	return (data->coefficients) ? (float)data->coefficients[3] : 0.0f;
-}
-
-void FModGenFunc_y_offset_set(PointerRNA *ptr, float value)
-{
-	FModifier *fcm = (FModifier *)(ptr->data);
-	FMod_Generator *data= (FMod_Generator*)(fcm->data);
-	if (data->coefficients) data->coefficients[3]= value;
-}
-
 /* --------- */
 
 StructRNA *rna_FModifierType_refine(struct PointerRNA *ptr)
@@ -118,13 +63,12 @@ StructRNA *rna_FModifierType_refine(struct PointerRNA *ptr)
 				case FCM_GENERATOR_POLYNOMIAL:
 					return &RNA_FModifierGenerator_PolyExpanded;
 				//case FCM_GENERATOR_POLYNOMIAL_FACTORISED:
-				case FCM_GENERATOR_FUNCTION:
-					return &RNA_FModifierGenerator_Function;
-				//case FCM_GENERATOR_EXPRESSION:
 				default:
 					return &RNA_FModifierGenerator;
 			}
 		}
+		case FMODIFIER_TYPE_FN_GENERATOR:
+			return &RNA_FModifierFunctionGenerator;
 		case FMODIFIER_TYPE_ENVELOPE:
 			return &RNA_FModifierEnvelope;
 		case FMODIFIER_TYPE_CYCLES:
@@ -222,8 +166,6 @@ static void rna_def_fmodifier_generator_common(StructRNA *srna)
 	static EnumPropertyItem prop_mode_items[] = {
 		{FCM_GENERATOR_POLYNOMIAL, "POLYNOMIAL", 0, "Expanded Polynomial", ""},
 		{FCM_GENERATOR_POLYNOMIAL_FACTORISED, "POLYNOMIAL_FACTORISED", 0, "Factorised Polynomial", ""},
-		{FCM_GENERATOR_FUNCTION, "FUNCTION", 0, "Built-In Function", ""},
-		{FCM_GENERATOR_EXPRESSION, "EXPRESSION", 0, "Expression", ""},
 		{0, NULL, 0, NULL, NULL}};
 		
 	/* struct wrapping settings */
@@ -273,7 +215,7 @@ static void rna_def_fmodifier_generator_polyexpanded(BlenderRNA *brna)
 	//RNA_def_property_ui_text(prop, "Coefficients", "Coefficients for 'x' (starting from lowest power).");
 }
 
-static void rna_def_fmodifier_generator_function(BlenderRNA *brna)
+static void rna_def_fmodifier_function_generator(BlenderRNA *brna)
 {
 	StructRNA *srna;
 	PropertyRNA *prop;
@@ -286,35 +228,32 @@ static void rna_def_fmodifier_generator_function(BlenderRNA *brna)
 		{4, "LN", 0, "Natural Logarithm", ""},
 		{5, "SINC", 0, "Normalised Sine", "sin(x) / x"},
 		{0, NULL, 0, NULL, NULL}};
-		
-	
-	srna= RNA_def_struct(brna, "FModifierGenerator_Function", "FModifier");
-	RNA_def_struct_ui_text(srna, "Built-In Function Generator", "Generates values for modified F-Curve using Built-In Function.");
-	
-	/* common settings */
-	rna_def_fmodifier_generator_common(srna);
 	
-	/* type */
-	prop= RNA_def_property(srna, "func_type", PROP_ENUM, PROP_NONE);
-	RNA_def_property_enum_items(prop, prop_type_items);
-	RNA_def_property_ui_text(prop, "Type", "Type of Built-In function to use as generator.");
+	srna= RNA_def_struct(brna, "FModifierFunctionGenerator", "FModifier");
+	RNA_def_struct_ui_text(srna, "Built-In Function F-Curve Modifier", "Generates values using a Built-In Function.");
+	RNA_def_struct_sdna_from(srna, "FMod_FunctionGenerator", "data");
 	
 	/* coefficients */
 	prop= RNA_def_property(srna, "amplitude", PROP_FLOAT, PROP_NONE);
-	RNA_def_property_float_funcs(prop, "FModGenFunc_amplitude_get", "FModGenFunc_amplitude_set", NULL);
-	RNA_def_property_ui_text(prop, "Amplitude", "Scale factor for y-values generated by the function.");
+	RNA_def_property_ui_text(prop, "Amplitude", "Scale factor determining the maximum/minimum values.");
+	
+	prop= RNA_def_property(srna, "phase_multiplier", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_ui_text(prop, "Phase Multiplier", "Scale factor determining the 'speed' of the function.");
 	
-	prop= RNA_def_property(srna, "pre_multiplier", PROP_FLOAT, PROP_NONE);
-	RNA_def_property_float_funcs(prop, "FModGenFunc_pre_multiplier_get", "FModGenFunc_pre_multiplier_set", NULL);
-	RNA_def_property_ui_text(prop, "PreMultiplier", "Scale factor for x-value inputs to function.");
+	prop= RNA_def_property(srna, "phase_offset", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_ui_text(prop, "Phase Offset", "Constant factor to offset time by for function.");
 	
-	prop= RNA_def_property(srna, "x_offset", PROP_FLOAT, PROP_NONE);
-	RNA_def_property_float_funcs(prop, "FModGenFunc_x_offset_get", "FModGenFunc_x_offset_set", NULL);
-	RNA_def_property_ui_text(prop, "X Offset", "Offset for x-value inputs to function.");
+	prop= RNA_def_property(srna, "value_offset", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_ui_text(prop, "Value Offset", "Constant factor to offset values by.");
 	
-	prop= RNA_def_property(srna, "y_offset", PROP_FLOAT, PROP_NONE);
-	RNA_def_property_float_funcs(prop, "FModGenFunc_y_offset_get", "FModGenFunc_y_offset_set", NULL);
-	RNA_def_property_ui_text(prop, "Y Offset", "Offset for y-values generated by the function.");
+	/* flags */
+	prop= RNA_def_property(srna, "additive", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_sdna(prop, NULL, "flag", FCM_GENERATOR_ADDITIVE);
+	RNA_def_property_ui_text(prop, "Additive", "Values generated by this modifier are applied on top of the existing values instead of overwriting them.");
+	
+	prop= RNA_def_property(srna, "type", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_items(prop, prop_type_items);
+	RNA_def_property_ui_text(prop, "Type", "Type of built-in function to use.");
 }
 
 /* --------- */
@@ -646,7 +585,7 @@ void RNA_def_fcurve(BlenderRNA *brna)
 	
 	rna_def_fmodifier_generator(brna);
 		rna_def_fmodifier_generator_polyexpanded(brna);
-		rna_def_fmodifier_generator_function(brna);
+	rna_def_fmodifier_function_generator(brna);
 	rna_def_fmodifier_envelope(brna);
 	rna_def_fmodifier_cycles(brna);
 	rna_def_fmodifier_python(brna);