Adapt G26 to work for all meshes

Marlin/src/feature/bedlevel/bedlevel.h

@@ -23,14 +23,17 @@
 #ifndef __BEDLEVEL_H__
 #define __BEDLEVEL_H__
 
-#include "../../inc/MarlinConfig.h"
+#include "../../inc/MarlinConfigPre.h"
 
-#if ENABLED(MESH_BED_LEVELING)
-  #include "mbl/mesh_bed_leveling.h"
-#elif ENABLED(AUTO_BED_LEVELING_UBL)
-  #include "ubl/ubl.h"
-#elif HAS_ABL
-  #include "abl/abl.h"
+typedef struct {
+  int8_t x_index, y_index;
+  float distance; // When populated, the distance from the search location
+} mesh_index_pair;
+
+#if ENABLED(G26_MESH_VALIDATION)
+  extern bool g26_debug_flag;
+#else
+  constexpr bool g26_debug_flag = false;
 #endif
 
 #if ENABLED(PROBE_MANUALLY)
@@ -68,4 +71,23 @@ void reset_bed_level();
   void out_of_range_error(const char* p_edge);
 #endif
 
+#if ENABLED(AUTO_BED_LEVELING_BILINEAR)
+  #define _GET_MESH_X(I) bilinear_start[X_AXIS] + I * bilinear_grid_spacing[X_AXIS]
+  #define _GET_MESH_Y(J) bilinear_start[Y_AXIS] + J * bilinear_grid_spacing[Y_AXIS]
+#elif ENABLED(AUTO_BED_LEVELING_UBL)
+  #define _GET_MESH_X(I) ubl.mesh_index_to_xpos(I)
+  #define _GET_MESH_Y(J) ubl.mesh_index_to_ypos(J)
+#elif ENABLED(MESH_BED_LEVELING)
+  #define _GET_MESH_X(I) mbl.index_to_xpos[I]
+  #define _GET_MESH_Y(J) mbl.index_to_ypos[J]
+#endif
+
+#if ENABLED(MESH_BED_LEVELING)
+  #include "mbl/mesh_bed_leveling.h"
+#elif ENABLED(AUTO_BED_LEVELING_UBL)
+  #include "ubl/ubl.h"
+#elif HAS_ABL
+  #include "abl/abl.h"
+#endif
+
 #endif // __BEDLEVEL_H__