Documentation.

source/blender/include/BIF_butspace.h

@@ -134,7 +134,89 @@ extern void validate_editbonebutton_cb(void *bonev, void *namev);
 #define X4CLM2		77
 #define X4CLM3		165
 #define X4CLM4		232
- 
+
+#if 0
+/* start buttons grid doc/reclacement version
+/* With this system rows can easily have 1 to 4 buttons
+   or create perfectly aligned 1 to 4 columns layouts
+
+     < - - -    PANEL_XMAX  - - - >|
+     < - - -      PANELX     - - - >
+
+      .--  XSPACE side padding  --.
+      |                           |
+      |.- All CLM1                |
+      ||     X2CLM2 -.  X3CLM3    |
+      ||             |    |       |
+     +v|-------------|----|-------v+
+     <-/             |    |        |
+     | [           But1          ] |     1 button of BUTW1 size
+     <-             -/    |        |
+     | [   But1    ]=[   But2    ] |     2 buttons of BUTW2 size
+     <-                  -/        |
+  v  | [ But1  ]=[ But2 ]#[ But3 ] |     3 buttons of BUTW3 size
+  |  |                             |  v
+  ^  | [But1]#[But2]=[But3]#[But4] |  |  4 buttons of BUTW3 size
+  |  <-      ^      ^      -\      |  ^
+  |  +-------|------|-------|------+  |
+  |          |      |       |         |
+  '- YSPACE  '---.--'       '- X4CLM4 '- BUTH
+ (row to row)    |
+              Padding based in XSPACE (= normal, # +1 pix to make all match)
+
+   Calls like uiBlockBeginAlign/uiBlockEndAlign will make the button
+   to button space disappear if needed, forming a compact group, in some themes
+
+   TODO: Figure relations, meaning and usage of
+         PANELY, PANEL_YMAX, PANELW, PANELH
+ */
+#define PANELX		320
+#define PANELY		0
+#define PANELW		318
+#define PANELH		204
+
+#define XSPACE		10
+#define YSPACE		6
+#define PANEL_XMAX	(PANELX - XSPACE)
+#define PANEL_YMAX	210
+
+/* The widths follow 300, 150, 100 and 75, which is nice (discarding spacing)
+   sadly spacers and integer rounding make 3 and 4 column complex cases
+   so they better be manually set and checked following the comments */
+#define BUTW1		(PANELX - (2 * XSPACE))
+#define BUTW2		((BUTW1 / 2) - XSPACE)
+/* Manual calc so BUTW3 + XSPACE + BUTW3 + (XSPACE+1) + BUTW3 = BUTW1
+   Could be something like ((BUTW1/3)-(1+(2*XSPACE)) if starting with 300 */
+#define BUTW3		93
+/* This time BUTW4 + (XSPACE+1) + BUTW4 + XSPACE + BUTW4 + (XSPACE+1) + BUTW4 = BUTW1
+   That would be ((BUTW1/4)-(2+(3*XSPACE)) if starting with 300 */
+#define BUTW4		67
+/* NOTE: Again, BUTW3 and BUTW4 values and formulas include manual tuning,
+   retune if base BUTW1 stops being 300 pixels. You have been warned */
+#define ICONBUTW	20
+#define BUTH		22
+
+/* X axis start positions of column presets
+   First number declares how many columns total
+   Second number declares the exact column it controls
+   So X3CLM2 means X start position of 2nd button for a row of 3 buttons */
+#define X1CLM1		XSPACE
+
+#define X2CLM1		X1CLM1
+#define X2CLM2		(X2CLM1 + BUTW2 + XSPACE)
+
+#define X3CLM1		X1CLM1
+#define X3CLM2		(X3CLM1 + BUTW3 + XSPACE)
+/* By substracting from end we already get the extra 1 pix */
+#define X3CLM3		(PANEL_XMAX - BUTW3)
+
+#define X4CLM1		X1CLM1
+/* Extra pix to reach the BUTW1 total size */
+#define X4CLM2		(X4CLM1 + BUTW4 + XSPACE + 1)
+#define X4CLM3		(X4CLM2 + BUTW4 + XSPACE)
+/* By substracting from end we already get the other extra 1 pix */
+#define X4CLM4		(PANEL_XMAX - BUTW4)
+/* end buttons grid doc/replacement version */
+#endif /* if 0 */
 
 #endif
-