Bugfix #25657

Three code fixes for 1 report. User experienced crashes while
painting on float buffer + having preview renders on.

- Texture Nodes: Image was re-allocated without using
  proper thread lock
- Paint code: old convention to free the byte rect from
  a float image as signal to re-create now is a proper
  flag. This keeps image memory unchanged. Nice for render.
- Imbuf: call to make a byte rect from float was freeing
  mipmaps unnecessary.

3 files changed, 5 insertions, 7 deletions

diff --git a/source/blender/imbuf/IMB_imbuf_types.h b/source/blender/imbuf/IMB_imbuf_types.h
index f60c6d03547..5629ead80db 100644
--- a/source/blender/imbuf/IMB_imbuf_types.h
+++ b/source/blender/imbuf/IMB_imbuf_types.h
@@ -137,12 +137,7 @@ typedef struct ImBuf {
 #define IB_BITMAPFONT		(1 << 0)	/* this image is a font */
 #define IB_BITMAPDIRTY		(1 << 1)	/* image needs to be saved is not the same as filename */
 #define IB_MIPMAP_INVALID	(1 << 2)	/* image mipmaps are invalid, need recreate */
-
-/* From iff.h. This was once moved away by Frank, now Nzc moves it
- * back. Such is the way it is... It is a long list of defines, and
- * there are a few external defines in the back. Most of the stuff is
- * probably imbuf_intern only. This will need to be merged later
- * on. */
+#define IB_RECT_INVALID		(1 << 3)    /* float buffer changed, needs recreation of byte rect */
 
 /**
  * \name Imbuf Component flags
diff --git a/source/blender/imbuf/intern/allocimbuf.c b/source/blender/imbuf/intern/allocimbuf.c
index 17387c0a4d3..fa823169966 100644
--- a/source/blender/imbuf/intern/allocimbuf.c
+++ b/source/blender/imbuf/intern/allocimbuf.c
@@ -277,7 +277,8 @@ short imb_addrectfloatImBuf(ImBuf *ibuf)
 	
 	if(ibuf==NULL) return FALSE;
 	
-	imb_freerectfloatImBuf(ibuf);
+	if(ibuf->rect_float)
+		imb_freerectfloatImBuf(ibuf); /* frees mipmap too, hrm */
 	
 	size = ibuf->x *ibuf->y;
 	size = size *4 *sizeof(float);
diff --git a/source/blender/imbuf/intern/divers.c b/source/blender/imbuf/intern/divers.c
index 9e2c32765d2..9605185e897 100644
--- a/source/blender/imbuf/intern/divers.c
+++ b/source/blender/imbuf/intern/divers.c
@@ -188,6 +188,8 @@ void IMB_rect_from_float(struct ImBuf *ibuf)
 			}
 		}
 	}
+	/* ensure user flag is reset */
+	ibuf->userflags &= ~IB_RECT_INVALID;
 }
 
 static void imb_float_from_rect_nonlinear(struct ImBuf *ibuf, float *fbuf)