Bugfix #22040

Old bug report:

Image Editor, Painting: crash when texture was visible in 
Material or Texture preview. Was caused by paint code
freeing mipmaps. Now replaced with a mipmap tag (to be done
again), and a new mipmap function that doesn't re-allocate.

5 files changed, 62 insertions, 14 deletions

diff --git a/source/blender/imbuf/IMB_imbuf.h b/source/blender/imbuf/IMB_imbuf.h
index a22168e06a3..2accad35859 100644
--- a/source/blender/imbuf/IMB_imbuf.h
+++ b/source/blender/imbuf/IMB_imbuf.h
@@ -244,6 +244,7 @@ void IMB_filter(struct ImBuf *ibuf);
 void IMB_filterN(struct ImBuf *out, struct ImBuf *in);
 void IMB_filter_extend(struct ImBuf *ibuf, char *mask);
 void IMB_makemipmap(struct ImBuf *ibuf, int use_filter);
+void IMB_remakemipmap(struct ImBuf *ibuf, int use_filter);
 struct ImBuf *IMB_getmipmap(struct ImBuf *ibuf, int level);
 
 /**
diff --git a/source/blender/imbuf/IMB_imbuf_types.h b/source/blender/imbuf/IMB_imbuf_types.h
index a12976fa813..f60c6d03547 100644
--- a/source/blender/imbuf/IMB_imbuf_types.h
+++ b/source/blender/imbuf/IMB_imbuf_types.h
@@ -131,11 +131,12 @@ typedef struct ImBuf {
 
 /* Moved from BKE_bmfont_types.h because it is a userflag bit mask. */
 /**
- * \brief Flags used internally by blender for imagebuffers
+ * \brief userflags: Flags used internally by blender for imagebuffers
  */
 
 #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
diff --git a/source/blender/imbuf/intern/IMB_filter.h b/source/blender/imbuf/intern/IMB_filter.h
index 84ad72c520a..0d414cb4702 100644
--- a/source/blender/imbuf/intern/IMB_filter.h
+++ b/source/blender/imbuf/intern/IMB_filter.h
@@ -44,5 +44,7 @@ void imb_filterx(struct ImBuf *ibuf);
 void IMB_premultiply_rect(unsigned int *rect, int depth, int w, int h);
 void IMB_premultiply_rect_float(float *rect_float, int depth, int w, int h);
 
+void imb_onehalf_no_alloc(struct ImBuf *ibuf2, struct ImBuf *ibuf1);
+
 #endif
 
diff --git a/source/blender/imbuf/intern/filter.c b/source/blender/imbuf/intern/filter.c
index 3c2c276b6e4..13c0e6cf632 100644
--- a/source/blender/imbuf/intern/filter.c
+++ b/source/blender/imbuf/intern/filter.c
@@ -371,11 +371,48 @@ void IMB_filter_extend(struct ImBuf *ibuf, char *mask)
 	}
 }
 
+/* threadsafe version, only recreates existing maps */
+void IMB_remakemipmap(ImBuf *ibuf, int use_filter)
+{
+	ImBuf *hbuf = ibuf;
+	int curmap = 0;
+	
+	ibuf->miptot= 1;
+	
+	while(curmap < IB_MIPMAP_LEVELS) {
+		
+		if(ibuf->mipmap[curmap]) {
+			
+			if(use_filter) {
+				ImBuf *nbuf= IMB_allocImBuf(hbuf->x, hbuf->y, 32, IB_rect);
+				IMB_filterN(nbuf, hbuf);
+				imb_onehalf_no_alloc(ibuf->mipmap[curmap], nbuf);
+				IMB_freeImBuf(nbuf);
+			}
+			else
+				imb_onehalf_no_alloc(ibuf->mipmap[curmap], hbuf);
+		}
+		
+		ibuf->miptot= curmap+2;
+		hbuf= ibuf->mipmap[curmap];
+		if(hbuf)
+			hbuf->miplevel= curmap+1;
+		
+		if(!hbuf || (hbuf->x <= 2 && hbuf->y <= 2))
+			break;
+		
+		curmap++;
+	}
+}
+
+/* frees too (if there) and recreates new data */
 void IMB_makemipmap(ImBuf *ibuf, int use_filter)
 {
 	ImBuf *hbuf = ibuf;
 	int curmap = 0;
 
+	imb_freemipmapImBuf(ibuf);
+	
 	ibuf->miptot= 1;
 
 	while(curmap < IB_MIPMAP_LEVELS) {
diff --git a/source/blender/imbuf/intern/scaling.c b/source/blender/imbuf/intern/scaling.c
index 73dcc0c8ea9..1f50deaee2a 100644
--- a/source/blender/imbuf/intern/scaling.c
+++ b/source/blender/imbuf/intern/scaling.c
@@ -286,26 +286,16 @@ struct ImBuf *IMB_double_y(struct ImBuf *ibuf1)
 	return (ibuf2);
 }
 
-
-struct ImBuf *IMB_onehalf(struct ImBuf *ibuf1)
+/* result in ibuf2, scaling should be done correctly */
+void imb_onehalf_no_alloc(struct ImBuf *ibuf2, struct ImBuf *ibuf1)
 {
-	struct ImBuf *ibuf2;
 	uchar *p1, *p2 = NULL, *dest;
 	float *p1f, *destf, *p2f = NULL;
 	int x,y;
 	int do_rect, do_float;
 
-	if (ibuf1==NULL) return (0);
-	if (ibuf1->rect==NULL && ibuf1->rect_float==NULL) return (0);
-
 	do_rect= (ibuf1->rect != NULL);
-
-	if (ibuf1->x <= 1) return(IMB_half_y(ibuf1));
-	if (ibuf1->y <= 1) return(IMB_half_x(ibuf1));
 	
-	ibuf2=IMB_allocImBuf((ibuf1->x)/2, (ibuf1->y)/2, ibuf1->depth, ibuf1->flags);
-	if (ibuf2==NULL) return (0);
-
 	p1f = ibuf1->rect_float;
 	destf=ibuf2->rect_float;
 	p1 = (uchar *) ibuf1->rect;
@@ -343,9 +333,26 @@ struct ImBuf *IMB_onehalf(struct ImBuf *ibuf1)
 			if (do_float) p1f+=4;
 		}
 	}
-	return (ibuf2);
+	
 }
 
+struct ImBuf *IMB_onehalf(struct ImBuf *ibuf1)
+{
+	struct ImBuf *ibuf2;
+
+	if (ibuf1==NULL) return (0);
+	if (ibuf1->rect==NULL && ibuf1->rect_float==NULL) return (0);
+	
+	if (ibuf1->x <= 1) return(IMB_half_y(ibuf1));
+	if (ibuf1->y <= 1) return(IMB_half_x(ibuf1));
+	
+	ibuf2=IMB_allocImBuf((ibuf1->x)/2, (ibuf1->y)/2, ibuf1->depth, ibuf1->flags);
+	if (ibuf2==NULL) return (0);
+	
+	imb_onehalf_no_alloc(ibuf2, ibuf1);
+	
+	return (ibuf2);
+}
 
 /* q_scale_linear_interpolation helper functions */