Orange branch feature; Material Layering

(WIP, don't bugs for this in tracker yet please!)

- New Panel "Layers" in Material buttons, allows to add unlimited amount
  of materials on top of each other.
- Every Layer is actually just another Material, which gets rendered/shaded
  (including texture), and then added on top of previous layer with an
  operation like Mix, Add, Mult, etc.
- Layers render fully independent, so bumpmaps are not passed on to next
  layers.
- Per Layer you can set if it influences Diffuse, Specular or Alpha
- If a Material returns alpha (like from texture), the alpha value is
  used for adding the layers too.
- New texture "Map To" channel allows to have a texture work on a Layer
- Each layer, including basis Material, can be turned on/off individually

Notes:

- at this moment, the full shading pass happens for each layer, including
  shadow, AO and raytraced mirror or transparency...
- I had to remove old hacks from preview render, which corrected reflected
  normals for preview texturing.
- still needs loadsa testing!

1 files changed, 29 insertions, 9 deletions

diff --git a/source/blender/makesdna/DNA_material_types.h b/source/blender/makesdna/DNA_material_types.h
index 5ef327502e1..395c438c6e3 100644
--- a/source/blender/makesdna/DNA_material_types.h
+++ b/source/blender/makesdna/DNA_material_types.h
@@ -34,10 +34,9 @@
 #ifndef DNA_MATERIAL_TYPES_H
 #define DNA_MATERIAL_TYPES_H
 
-/*  #include "BLI_listBase.h" */
-
 #include "DNA_ID.h"
 #include "DNA_scriptlink_types.h"
+#include "DNA_listBase.h"
 
 #ifndef MAX_MTEX
 #define MAX_MTEX	10
@@ -48,20 +47,32 @@ struct Ipo;
 struct Material;
 struct ColorBand;
 
+typedef struct MaterialLayer {
+	struct MaterialLayer *next, *prev;
+	
+	struct Material *mat;
+	float blendfac;
+	short flag, blendmethod, menunr, pad;
+	int pad2;
+	
+} MaterialLayer;
+
 /* WATCH IT: change type? also make changes in ipo.h  */
 
 typedef struct Material {
 	ID id;
 	
 	short colormodel, lay;		/* lay: for dynamics (old engine, until 2.04) */
+	/* note, keep this below synced with render_types.h */
 	float r, g, b;
 	float specr, specg, specb;
 	float mirr, mirg, mirb;
 	float ambr, ambb, ambg;
-	
 	float amb, emit, ang, spectra, ray_mirror;
 	float alpha, ref, spec, zoffs, add;
 	float translucency;
+	/* end synced with render_types.h */
+	
 	float fresnel_mir, fresnel_mir_i;
 	float fresnel_tra, fresnel_tra_i;
 	float filter;		/* filter added, for raytrace transparency */
@@ -69,16 +80,15 @@ typedef struct Material {
 	short har;
 	char seed1, seed2;
 	
-	int mode; 
-	int mode2; /* even more material settings :) */
+	int mode, mode_l;		/* mode_l is the or-ed result of all layer modes */
 	short flarec, starc, linec, ringc;
 	float hasize, flaresize, subsize, flareboost;
 	float strand_sta, strand_end, strand_ease;
+	float pad1;
 	
 	/* for buttons and render*/
 	char rgbsel, texact, pr_type, pad;
-	short pr_back, pr_lamp, septex, pad4;
-	int pad5;
+	short pr_back, pr_lamp, septex, ml_flag;	/* ml_flag is for disable base material */
 	
 	/* shaders */
 	short diff_shader, spec_shader;
@@ -97,6 +107,7 @@ typedef struct Material {
 	float rampfac_col, rampfac_spec;
 
 	struct MTex *mtex[10];
+	ListBase layers;
 	struct Ipo *ipo;
 	
 	/* dynamic properties */
@@ -107,7 +118,7 @@ typedef struct Material {
 	/* yafray: absorption color, dispersion parameters and material preset menu */
 	float YF_ar, YF_ag, YF_ab, YF_dscale, YF_dpwr;
 	int YF_dsmp, YF_preset, YF_djit;
-
+	
 	ScriptLink scriptlink;
 } Material;
 
@@ -161,7 +172,7 @@ typedef struct Material {
 #define MA_DIFF_LAMBERT		0
 #define MA_DIFF_ORENNAYAR	1
 #define MA_DIFF_TOON		2
-#define MA_DIFF_MINNAERT        3
+#define MA_DIFF_MINNAERT    3
 
 /* spec_shader */
 #define MA_SPEC_COOKTORR	0
@@ -224,6 +235,7 @@ typedef struct Material {
 #define MAP_AMB			2048
 #define MAP_DISPLACE	4096
 #define MAP_WARP		8192
+#define MAP_LAYER		16384
 
 /* pr_type */
 #define MA_FLAT			0
@@ -233,5 +245,13 @@ typedef struct Material {
 /* pr_back */
 #define MA_DARK			1
 
+/* MaterialLayer flag */
+#define ML_ACTIVE		1
+#define ML_RENDER		2
+#define ML_NEG_NORMAL	4
+#define ML_DIFFUSE		8
+#define ML_SPECULAR		16
+#define ML_ALPHA		32
+
 #endif