"UV Test Grid" option in Image Window > Image menu > New, to generate

a colored grid instead of a blank image, for quickly spotting distortion
in UV maps.

3 files changed, 32 insertions, 8 deletions

diff --git a/source/blender/blenkernel/BKE_image.h b/source/blender/blenkernel/BKE_image.h
index 1927ad9bb02..1ae5552104c 100644
--- a/source/blender/blenkernel/BKE_image.h
+++ b/source/blender/blenkernel/BKE_image.h
@@ -47,7 +47,7 @@ void free_image(struct Image *me);
 void free_image_buffers(struct Image *ima);
 struct Image *add_image(char *name);
 void free_unused_animimages(void);
-struct Image *new_image(int width, int height, char *name);
+struct Image *new_image(int width, int height, char *name, short uvtestgrid);
 
 void makepicstring(char *string, int frame);
 void addImageExtension(char *string);
diff --git a/source/blender/blenkernel/intern/image.c b/source/blender/blenkernel/intern/image.c
index 5be1c0ed48f..c09f68643ce 100644
--- a/source/blender/blenkernel/intern/image.c
+++ b/source/blender/blenkernel/intern/image.c
@@ -54,6 +54,7 @@
 #include "DNA_userdef_types.h"
 
 #include "BLI_blenlib.h"
+#include "BLI_arithb.h"
 
 #include "BKE_bmfont.h"
 #include "BKE_packedFile.h"
@@ -148,7 +149,7 @@ Image *add_image(char *name)
 	return ima;
 }
 
-Image *new_image(int width, int height, char *name)
+Image *new_image(int width, int height, char *name, short uvtestgrid)
 {
 	Image *ima;
 			
@@ -159,6 +160,7 @@ Image *new_image(int width, int height, char *name)
 		ImBuf *ibuf;
 		unsigned char *rect;
 		int x, y;
+		float h=0.0, hoffs=0.0, s=0.9, v=0.6, r, g, b;
 
 		strcpy(ima->name, "Untitled");
 
@@ -167,10 +169,30 @@ Image *new_image(int width, int height, char *name)
 		ima->ibuf= ibuf;
 
 		rect= (unsigned char*)ibuf->rect;
-		for(y=0; y<ibuf->y; y++) {
-			for(x=0; x<ibuf->x; x++, rect+=4) {
-				rect[0]= rect[1]= rect[2]= 0;
-				rect[3]= 255;
+		
+		if (uvtestgrid) {
+			for(y=0; y<ibuf->y; y++) {
+				if (y % 20 == 0) hoffs += 0.125;
+				if (y % 160 == 0) hoffs = 0.0;
+				
+				for(x=0; x<ibuf->x; x++, rect+=4) {
+					if (x % 20 == 0) h += 0.125;
+					if (x % 160 == 0) h = 0.0;
+								
+					hsv_to_rgb(fabs(h-hoffs), s, v, &r, &g, &b);
+					
+					rect[0]= (char)(r * 255.0);
+					rect[1]= (char)(g * 255.0);
+					rect[2]= (char)(b * 255.0);
+					rect[3]= 255;
+				}
+			}
+		} else {	/* blank image */
+			for(y=0; y<ibuf->y; y++) {
+				for(x=0; x<ibuf->x; x++, rect+=4) {
+					rect[0]= rect[1]= rect[2]= 0;
+					rect[3]= 255;
+				}
 			}
 		}
 
diff --git a/source/blender/src/header_image.c b/source/blender/src/header_image.c
index 8a4603ec532..e0571e94e45 100644
--- a/source/blender/src/header_image.c
+++ b/source/blender/src/header_image.c
@@ -731,6 +731,7 @@ static void do_image_imagemenu(void *arg, int event)
 	case 7: /* New Image */
 		{
 			static int width= 256, height= 256;
+			static short uvtestgrid=0;
 			char name[256];
 
 			strcpy(name, "Image");
@@ -738,10 +739,11 @@ static void do_image_imagemenu(void *arg, int event)
 			add_numbut(0, TEX, "Name:", 0, 255, name, NULL);
 			add_numbut(1, NUM|INT, "Width:", 1, 5000, &width, NULL);
 			add_numbut(2, NUM|INT, "Height:", 1, 5000, &height, NULL);
-			if (!do_clever_numbuts("New Image", 3, REDRAW))
+			add_numbut(3, TOG|SHO, "UV Test Grid", 0, 0, &uvtestgrid, NULL);
+			if (!do_clever_numbuts("New Image", 4, REDRAW))
 				return;
 
-			G.sima->image= new_image(width, height, name);
+			G.sima->image= new_image(width, height, name, uvtestgrid);
 			image_changed(G.sima, 0);
 
 			allqueue(REDRAWIMAGE, 0);