更新 sant 支持大于和小于屏幕尺寸图片显示，及位置

boards/default_src/micropython_esp32s3/origin/build/lib/st7789_cf.py

@@ -34,15 +34,38 @@ class ST7789(uframebuf.FrameBuffer_Uincode):
         self._oneclight = True
         self._backlight = backlight
 
-    def display(self, data=None, rotation=0, sync=True):
+    def display(self, data=None, x=None, y=None, rotation=0, sync=True):
         if type(data) is str:
             data = Image.open(data, rotation)
-        self._buffer[:] = data.image  # 后期做图像尺寸匹配处理
+        self._blit(data, x, y)
         if sync: self.show()
 
     def screenshot(self):
         return IMG(memoryview(self._buffer), self.width, self.height)
 
+    def _blit(self, img, x=None, y=None):
+        '''考虑后期封装C模块，加快速度'''
+        if img.width == self.width and img.height == self.height:
+            self._buffer[:] = img.image
+        #大于屏幕图像
+        elif img.width > self.width and img.height > self.height:
+            _x = ((img.width - self.width) // 2) if x is None else max(0, min(x, img.width - self.width))
+            _y = ((img.height - self.height) // 2) if y is None else max(0, min(y, img.height - self.height))
+            for line in range(self.height):
+                src_pos =  ((_y + line) * img.width + _x) * 2
+                dst_pos = line * self.width * 2
+                self._buffer[dst_pos:dst_pos + self.width * 2] = img.image[src_pos:src_pos + self.width * 2]
+        #小于屏幕图像
+        elif img.width < self.width and img.height < self.height:
+            _x = ((self.width - img.width) // 2) if x is None else max(0, min(x, self.width - img.width))
+            _y = ((self.height- img.height) // 2) if y is None else max(0, min(y, self.height - img.width))
+            for line in range(img.height):
+                src_pos = line * img.width * 2
+                dst_pos = ((_y + line) * self.width + _x) * 2
+                self._buffer[dst_pos:dst_pos + img.width * 2] = img.image[src_pos:src_pos + img.width * 2]
+        else:
+            raise ValueError("Unsupported image size for display")
+
     def _write(self, cmd, dat=None):
         self.dc.off()
         self.spi.write(bytearray([cmd]))