From 273a9196ebefdd455c6773682abff79a328f9277 Mon Sep 17 00:00:00 2001
From: Veka0 <26331365+Veka0@users.noreply.github.com>
Date: Thu, 3 Jul 2025 12:13:17 +0200
Subject: [PATCH] Improve blending factors documentation

---
 src/gu/pspgu.h               | 44 +++++++++++++++++++++---------------
 src/samples/gu/blend/blend.c |  2 +-
 2 files changed, 27 insertions(+), 19 deletions(-)

diff --git a/src/gu/pspgu.h b/src/gu/pspgu.h
index 35b274c6..d577d66d 100644
--- a/src/gu/pspgu.h
+++ b/src/gu/pspgu.h
@@ -249,15 +249,21 @@ extern "C" {
 #define GU_ABS			(5)
 
 /* Blending Factor */
-#define GU_SRC_COLOR		(0)
-#define GU_ONE_MINUS_SRC_COLOR	(1)
-#define GU_SRC_ALPHA		(2)
-#define GU_ONE_MINUS_SRC_ALPHA	(3)
-#define GU_DST_COLOR		(0)
-#define GU_ONE_MINUS_DST_COLOR	(1)
-#define GU_DST_ALPHA		(4)
-#define GU_ONE_MINUS_DST_ALPHA	(5)
-#define GU_FIX			(10)
+#define GU_OTHER_COLOR                (0)
+#define GU_ONE_MINUS_OTHER_COLOR      (1)
+#define GU_SRC_ALPHA                  (2)
+#define GU_ONE_MINUS_SRC_ALPHA        (3)
+#define GU_DST_ALPHA                  (4)
+#define GU_ONE_MINUS_DST_ALPHA        (5)
+#define GU_DOUBLE_SRC_ALPHA           (6)
+#define GU_ONE_MINUS_DOUBLE_SRC_ALPHA (7)
+#define GU_DOUBLE_DST_ALPHA           (8)
+#define GU_ONE_MINUS_DOUBLE_DST_ALPHA (9)
+#define GU_FIX                        (10) /* Note: behavior of 11-15 blend factors is identical to GU_FIX */
+#define GU_SRC_COLOR           (0) /* Deprecated */
+#define GU_ONE_MINUS_SRC_COLOR (1) /* Deprecated */
+#define GU_DST_COLOR           (0) /* Deprecated */
+#define GU_ONE_MINUS_DST_COLOR (1) /* Deprecated */
 
 /* Stencil Operations */
 #define GU_KEEP			(0)
@@ -1054,15 +1060,17 @@ void sceGuAmbientColor(unsigned int color);
   *   - GU_ABS - |Cs-Cd|
   *
   * Available blending-functions are:
-  *   - GU_SRC_COLOR
-  *   - GU_ONE_MINUS_SRC_COLOR
-  *   - GU_SRC_ALPHA
-  *   - GU_ONE_MINUS_SRC_ALPHA
-  *   - GU_DST_ALPHA
-  *   - GU_ONE_MINUS_DST_ALPHA
-  *   - GU_DST_COLOR
-  *   - GU_ONE_MINUS_DST_COLOR
-  *   - GU_FIX
+  *   - GU_OTHER_COLOR - dstColor if used for source operand; srcColor if used for destination operand
+  *   - GU_ONE_MINUS_OTHER_COLOR - 1-dstColor if used for source operand; 1-srcColor if used for destination operand
+  *   - GU_SRC_ALPHA - srcAlpha
+  *   - GU_ONE_MINUS_SRC_ALPHA - 1-srcAlpha
+  *   - GU_DST_ALPHA - dstAlpha
+  *   - GU_ONE_MINUS_DST_ALPHA - 1-dstAlpha
+  *   - GU_DOUBLE_SRC_ALPHA - 2*srcAlpha
+  *   - GU_ONE_MINUS_DOUBLE_SRC_ALPHA - 1-2*srcAlpha
+  *   - GU_DOUBLE_DST_ALPHA - 2*dstAlpha
+  *   - GU_ONE_MINUS_DOUBLE_DST_ALPHA - 1-2*dstAlpha
+  *   - GU_FIX - srcFix if used for source operand; dstFix if used for destination operand
   *
   * @param op - Blending Operation
   * @param src - Blending function for source operand
diff --git a/src/samples/gu/blend/blend.c b/src/samples/gu/blend/blend.c
index 2968d4d6..11146fbf 100644
--- a/src/samples/gu/blend/blend.c
+++ b/src/samples/gu/blend/blend.c
@@ -52,7 +52,7 @@ struct BlendState states[] =
 {
 	{"GU_ADD, GU_SRC_ALPHA, GU_ONE_MINUS_SRC_ALPHA", GU_ADD, GU_SRC_ALPHA, GU_ONE_MINUS_SRC_ALPHA, 0, 0},
 	{"GU_SUBTRACT, GU_SRC_ALPHA, GU_ONE_MINUS_SRC_ALPHA", GU_SUBTRACT, GU_SRC_ALPHA, GU_ONE_MINUS_SRC_ALPHA, 0, 0},
-	{"GU_ALPHA_ADD, GU_SRC_COLOR, GU_DST_COLOR", GU_ADD, GU_SRC_COLOR, GU_DST_COLOR, 0, 0},
+	{"GU_ALPHA_ADD, GU_OTHER_COLOR, GU_OTHER_COLOR", GU_ADD, GU_OTHER_COLOR, GU_OTHER_COLOR, 0, 0},
 	{"GU_ADD, GU_FIX(0x700f7f7f), GU_FIX(0x3f3f3f00)", GU_ADD, GU_FIX, GU_FIX, 0x7f007f7f, 0x3f3f3f00},
 	{"GU_ADD, GU_FIX(0x7f7f7f7f), GU_FIX(0x7f7f7f7f)", GU_ADD, GU_FIX, GU_FIX, 0x7f7f7f7f, 0x7f7f7f7f}
 };