[Bf-blender-cvs] [210d0f1b801] blender-v3.2-release: Fix T96414: Stencil mapping is incorrect for UDIMs

[Jesse Yurkovich]

Commit: 210d0f1b801fb23c7edabb35b67224eab671e363
Author: Jesse Yurkovich
Date:   Tue May 17 00:27:23 2022 -0700
Branches: blender-v3.2-release
https://developer.blender.org/rB210d0f1b801fb23c7edabb35b67224eab671e363

Fix T96414: Stencil mapping is incorrect for UDIMs

When texture painting, brush textures and brush texture masks were not
transformed to account for UDIM tiles.

Differential Revision: https://developer.blender.org/D14671

===================================================================

M	source/blender/editors/sculpt_paint/paint_image_2d.c

===================================================================

diff --git a/source/blender/editors/sculpt_paint/paint_image_2d.c b/source/blender/editors/sculpt_paint/paint_image_2d.c
index d30aa4dfab1..fae2e6863fa 100644
--- a/source/blender/editors/sculpt_paint/paint_image_2d.c
+++ b/source/blender/editors/sculpt_paint/paint_image_2d.c
@@ -621,39 +621,38 @@ static void brush_painter_imbuf_partial_update(BrushPainter *painter,
 }
 
 static void brush_painter_2d_tex_mapping(ImagePaintState *s,
-                                         ImBuf *canvas,
+                                         ImagePaintTile *tile,
                                          const int diameter,
-                                         const float startpos[2],
                                          const float pos[2],
                                          const float mouse[2],
                                          int mapmode,
                                          rctf *mapping)
 {
-  float invw = 1.0f / (float)canvas->x;
-  float invh = 1.0f / (float)canvas->y;
-  int xmin, ymin, xmax, ymax;
-  int ipos[2];
+  float invw = 1.0f / (float)tile->canvas->x;
+  float invh = 1.0f / (float)tile->canvas->y;
+  float start[2];
 
   /* find start coordinate of brush in canvas */
-  ipos[0] = (int)floorf((pos[0] - diameter / 2) + 1.0f);
-  ipos[1] = (int)floorf((pos[1] - diameter / 2) + 1.0f);
+  start[0] = pos[0] - diameter / 2.0f;
+  start[1] = pos[1] - diameter / 2.0f;
 
   if (mapmode == MTEX_MAP_MODE_STENCIL) {
     /* map from view coordinates of brush to region coordinates */
-    UI_view2d_view_to_region(s->v2d, ipos[0] * invw, ipos[1] * invh, &xmin, &ymin);
-    UI_view2d_view_to_region(
-        s->v2d, (ipos[0] + diameter) * invw, (ipos[1] + diameter) * invh, &xmax, &ymax);
+    float xmin, ymin, xmax, ymax;
+    UI_view2d_view_to_region_fl(s->v2d, start[0] * invw, start[1] * invh, &xmin, &ymin);
+    UI_view2d_view_to_region_fl(
+        s->v2d, (start[0] + diameter) * invw, (start[1] + diameter) * invh, &xmax, &ymax);
 
     /* output mapping from brush ibuf x/y to region coordinates */
-    mapping->xmin = xmin;
-    mapping->ymin = ymin;
     mapping->xmax = (xmax - xmin) / (float)diameter;
     mapping->ymax = (ymax - ymin) / (float)diameter;
+    mapping->xmin = xmin + (tile->uv_origin[0] * tile->size[0] * mapping->xmax);
+    mapping->ymin = ymin + (tile->uv_origin[1] * tile->size[1] * mapping->ymax);
   }
   else if (mapmode == MTEX_MAP_MODE_3D) {
     /* 3D mapping, just mapping to canvas 0..1. */
-    mapping->xmin = 2.0f * (ipos[0] * invw - 0.5f);
-    mapping->ymin = 2.0f * (ipos[1] * invh - 0.5f);
+    mapping->xmin = 2.0f * (start[0] * invw - 0.5f);
+    mapping->ymin = 2.0f * (start[1] * invh - 0.5f);
     mapping->xmax = 2.0f * invw;
     mapping->ymax = 2.0f * invh;
   }
@@ -665,8 +664,10 @@ static void brush_painter_2d_tex_mapping(ImagePaintState *s,
     mapping->ymax = 1.0f;
   }
   else /* if (mapmode == MTEX_MAP_MODE_TILED) */ {
-    mapping->xmin = (int)(-diameter * 0.5) + (int)floorf(pos[0]) - (int)floorf(startpos[0]);
-    mapping->ymin = (int)(-diameter * 0.5) + (int)floorf(pos[1]) - (int)floorf(startpos[1]);
+    mapping->xmin = (int)(-diameter * 0.5) + (int)floorf(pos[0]) -
+                    (int)floorf(tile->start_paintpos[0]);
+    mapping->ymin = (int)(-diameter * 0.5) + (int)floorf(pos[1]) -
+                    (int)floorf(tile->start_paintpos[1]);
     mapping->xmax = 1.0f;
     mapping->ymax = 1.0f;
   }
@@ -711,14 +712,8 @@ static void brush_painter_2d_refresh_cache(ImagePaintState *s,
       do_partial_update = true;
     }
 
-    brush_painter_2d_tex_mapping(s,
-                                 tile->canvas,
-                                 diameter,
-                                 tile->start_paintpos,
-                                 pos,
-                                 mouse,
-                                 brush->mtex.brush_map_mode,
-                                 &painter->tex_mapping);
+    brush_painter_2d_tex_mapping(
+        s, tile, diameter, pos, mouse, brush->mtex.brush_map_mode, &painter->tex_mapping);
   }
 
   if (cache->is_maskbrush) {
@@ -745,14 +740,8 @@ static void brush_painter_2d_refresh_cache(ImagePaintState *s,
         renew_maxmask) {
       MEM_SAFE_FREE(cache->tex_mask);
 
-      brush_painter_2d_tex_mapping(s,
-                                   tile->canvas,
-                                   diameter,
-                                   tile->start_paintpos,
-                                   pos,
-                                   mouse,
-                                   brush->mask_mtex.brush_map_mode,
-                                   &painter->mask_mapping);
+      brush_painter_2d_tex_mapping(
+          s, tile, diameter, pos, mouse, brush->mask_mtex.brush_map_mode, &painter->mask_mapping);
 
       if (do_partial_update_mask) {
         brush_painter_mask_imbuf_partial_update(painter, tile, pos, diameter);