fix [#27746] Black and White Render doesn't work and/or Saves as a Blank screen

convert to grayscale when saving renders rather then only writing the red channel.

2 files changed, 21 insertions, 0 deletions

diff --git a/source/blender/imbuf/IMB_imbuf.h b/source/blender/imbuf/IMB_imbuf.h
index e9592fdc164..ff01e3a8a1e 100644
--- a/source/blender/imbuf/IMB_imbuf.h
+++ b/source/blender/imbuf/IMB_imbuf.h
@@ -338,6 +338,7 @@ void IMB_float_from_rect_simple(struct ImBuf *ibuf); /* no profile conversion */
 /* note, check that the conversion exists, only some are supported */
 void IMB_convert_profile(struct ImBuf *ibuf, int profile);
 float *IMB_float_profile_ensure(struct ImBuf *ibuf, int profile, int *alloc);
+void IMB_color_to_bw(struct ImBuf *ibuf);
 
 /**
  * Change the ordering of the color bytes pointed to by rect from
diff --git a/source/blender/imbuf/intern/divers.c b/source/blender/imbuf/intern/divers.c
index 90ee2692cf0..7fc7669601d 100644
--- a/source/blender/imbuf/intern/divers.c
+++ b/source/blender/imbuf/intern/divers.c
@@ -490,3 +490,23 @@ float *IMB_float_profile_ensure(struct ImBuf *ibuf, int profile, int *alloc)
 		return fbuf;
 	}
 }
+
+
+/* no profile conversion */
+void IMB_color_to_bw(struct ImBuf *ibuf)
+{
+	float *rctf= ibuf->rect_float;
+	unsigned char *rct= (unsigned char *)ibuf->rect;
+	int i;
+	if(rctf) {
+		for (i = ibuf->x * ibuf->y; i > 0; i--, rctf+=4) {
+			rctf[0]= rctf[1]= rctf[2]= rgb_to_grayscale(rctf);
+		}
+	}
+
+	if(rct) {
+		for (i = ibuf->x * ibuf->y; i > 0; i--, rct+=4) {
+			rct[0]= rct[1]= rct[2]= rgb_to_grayscale_byte(rct);
+		}
+	}
+}