Added bitmap.blit function for bitmap slice copy

1 files changed, 7 insertions, 9 deletions

diff --git a/shared-module/displayio/Bitmap.c b/shared-module/displayio/Bitmap.c
index dde346ad3..dbcba6b58 100644
--- a/shared-module/displayio/Bitmap.c
+++ b/shared-module/displayio/Bitmap.c
@@ -106,26 +106,24 @@ uint32_t common_hal_displayio_bitmap_get_pixel(displayio_bitmap_t *self, int16_t
 }
 
 void common_hal_displayio_bitmap_blit(displayio_bitmap_t *self, int16_t x, int16_t y, displayio_bitmap_t *source,  
-                                        int16_t x1, int16_t y1, int16_t x2, int16_t y2) {
+                                        int16_t x1, int16_t y1, int16_t x2, int16_t y2, uint32_t skip_index, bool skip_index_none) {
     // Copy complete "source" bitmap into "self" bitmap at location x,y in the "self"
     // Add a boolean to determine if all values are copied, or only if non-zero
-    // Default is copy all values, but for text glyphs this should copy only non-zero values
+    // 
+    // If skip_value is encountered in the source bitmap, it will not be copied.  
+    // If skip_value is `None`, then all pixels are copied.
 
     if (self->read_only) {
         mp_raise_RuntimeError(translate("Read-only object"));
     }
 
-    // If this value is encountered in the source bitmap, it will not be copied (for text glyphs)
-    // This should be added as an optional parameter, and if it is `None`, then all pixels are copied
-    uint32_t skip_value=0;
-
     // simplest version - use internal functions for get/set pixels
-    for (uint16_t i=0; i<= (x2-x1) ; i++) {
+    for (int16_t i=0; i<= (x2-x1) ; i++) {
         if ( (x+i >= 0) && (x+i < self->width) ) {
-            for (uint16_t j=0; j<= (y2-y1) ; j++){
+            for (int16_t j=0; j<= (y2-y1) ; j++){
                 if ((y+j >= 0) && (y+j < self->height) ) {
                     uint32_t value = common_hal_displayio_bitmap_get_pixel(source, x1+i, y1+j);
-                    if ( (value != skip_value) ) { 
+                    if ( (skip_index_none) || (value != skip_index) ) { // write if skip_value_none is True
                             common_hal_displayio_bitmap_set_pixel(self, x+i, y+j, value);
                     }
                 }