import math
-from typing import Optional, Tuple
+import struct
+from typing import Optional, Tuple, BinaryIO
-from displayio import Bitmap
+from displayio import Bitmap, Colorspace
import circuitpython_typing
v += dv_row
rowu += du_col
rowv += dv_col
+
+
+def arrayblit(
+ bitmap: Bitmap,
+ data: circuitpython_typing.ReadableBuffer,
+ x1: int = 0, y1: int = 0,
+ x2: int | None = None, y2: int | None = None,
+ skip_index: int | None = None):
+ if x2 is None:
+ x2 = bitmap.width
+ if y2 is None:
+ y2 = bitmap.height
+
+ _value_count = 2 ** bitmap._bits_per_value
+ for y in range(y1, y2):
+ for x in range(x1, x2):
+ i = y * (x2 - x1) + x
+ value = int(data[i] % _value_count)
+ if skip_index is None or value != skip_index:
+ bitmap[x, y] = value
+
+
+def readinto(bitmap: Bitmap,
+ file: BinaryIO,
+ bits_per_pixel: int,
+ element_size: int = 1,
+ reverse_pixels_in_element: bool = False,
+ swap_bytes: bool = False,
+ reverse_rows: bool = False):
+
+ width = bitmap.width
+ height = bitmap.height
+ bits_per_value = bitmap._bits_per_value
+ mask = (1 << bits_per_value) - 1
+
+ elements_per_row = (width * bits_per_pixel + element_size * 8 - 1) // (element_size * 8)
+ rowsize = element_size * elements_per_row
+
+ for y in range(height):
+ row_bytes = file.read(rowsize)
+ if len(row_bytes) != rowsize:
+ raise EOFError()
+
+ # Convert the raw bytes into the appropriate type array for processing
+ rowdata = bytearray(row_bytes)
+
+ if swap_bytes:
+ if element_size == 2:
+ rowdata = bytearray(
+ b''.join(
+ struct.pack('<H', struct.unpack('>H', rowdata[i:i + 2])[0])
+ for i in range(0, len(rowdata), 2)
+ )
+ )
+ elif element_size == 4:
+ rowdata = bytearray(
+ b''.join(
+ struct.pack('<I', struct.unpack('>I', rowdata[i:i + 4])[0])
+ for i in range(0, len(rowdata), 4)
+ )
+ )
+
+ y_draw = height - 1 - y if reverse_rows else y
+
+ for x in range(width):
+ value = 0
+ if bits_per_pixel == 1:
+ byte_offset = x // 8
+ bit_offset = 7 - (x % 8) if reverse_pixels_in_element else x % 8
+ value = (rowdata[byte_offset] >> bit_offset) & 0x1
+ elif bits_per_pixel == 2:
+ byte_offset = x // 4
+ bit_index = 3 - (x % 4) if reverse_pixels_in_element else x % 4
+ bit_offset = 2 * bit_index
+ value = (rowdata[byte_offset] >> bit_offset) & 0x3
+ elif bits_per_pixel == 4:
+ byte_offset = x // 2
+ bit_index = 1 - (x % 2) if reverse_pixels_in_element else x % 2
+ bit_offset = 4 * bit_index
+ value = (rowdata[byte_offset] >> bit_offset) & 0xF
+ elif bits_per_pixel == 8:
+ value = rowdata[x]
+ elif bits_per_pixel == 16:
+ value = struct.unpack_from('<H', rowdata, x * 2)[0]
+ elif bits_per_pixel == 24:
+ offset = x * 3
+ value = (rowdata[offset] << 16) | (rowdata[offset + 1] << 8) | rowdata[offset + 2]
+ elif bits_per_pixel == 32:
+ value = struct.unpack_from('<I', rowdata, x * 4)[0]
+
+ bitmap[x, y_draw] = value & mask
+
+def alphablend(dest:Bitmap, source1:Bitmap, source2:Bitmap, colorspace:Colorspace, factor1:float, factor2:float,
+ blendmode, skip_source1_index:int=None,
+ skip_source2_index:int=None):
+
+ """
+ colorspace should be one of: 'L8', 'RGB565', 'RGB565_SWAPPED', 'BGR565_SWAPPED'.
+
+blendmode can be 'normal' (or any default) or 'screen'.
+
+This assumes that all bitmaps (dest, source1, source2) support 2D access like bitmap[x, y].
+
+dest.width and dest.height are used; make sure the bitmap objects have these attributes or replace them with your own logic.
+ """
+ def clamp(val, minval, maxval):
+ return max(minval, min(maxval, val))
+
+ ifactor1 = int(factor1 * 256)
+ ifactor2 = int(factor2 * 256)
+
+ width, height = dest.width, dest.height
+
+ if colorspace == 'L8':
+ for y in range(height):
+ for x in range(width):
+ sp1 = source1[x, y]
+ sp2 = source2[x, y]
+ blend_source1 = skip_source1_index is None or sp1 != skip_source1_index
+ blend_source2 = skip_source2_index is None or sp2 != skip_source2_index
+
+ if blend_source1 and blend_source2:
+ sda = sp1 * ifactor1
+ sca = sp2 * ifactor2
+
+ if blendmode == 'screen':
+ blend = sca + sda - (sca * sda // 65536)
+ else:
+ blend = sca + sda * (256 - ifactor2) // 256
+
+ denom = ifactor1 + ifactor2 - ifactor1 * ifactor2 // 256
+ pixel = blend // denom
+ elif blend_source1:
+ pixel = sp1 * ifactor1 // 256
+ elif blend_source2:
+ pixel = sp2 * ifactor2 // 256
+ else:
+ pixel = dest[x, y]
+
+ dest[x, y] = clamp(pixel, 0, 255)
+
+ else:
+ swap = colorspace in ('RGB565_SWAPPED', 'BGR565_SWAPPED')
+ r_mask = 0xf800
+ g_mask = 0x07e0
+ b_mask = 0x001f
+
+ for y in range(height):
+ for x in range(width):
+ sp1 = source1[x, y]
+ sp2 = source2[x, y]
+
+ if swap:
+ sp1 = ((sp1 & 0xFF) << 8) | ((sp1 >> 8) & 0xFF)
+ sp2 = ((sp2 & 0xFF) << 8) | ((sp2 >> 8) & 0xFF)
+
+ blend_source1 = skip_source1_index_none or sp1 != skip_source1_index
+ blend_source2 = skip_source2_index_none or sp2 != skip_source2_index
+
+ if blend_source1 and blend_source2:
+ ifactor_blend = ifactor1 + ifactor2 - ifactor1 * ifactor2 // 256
+
+ red_dca = ((sp1 & r_mask) >> 8) * ifactor1
+ grn_dca = ((sp1 & g_mask) >> 3) * ifactor1
+ blu_dca = ((sp1 & b_mask) << 3) * ifactor1
+
+ red_sca = ((sp2 & r_mask) >> 8) * ifactor2
+ grn_sca = ((sp2 & g_mask) >> 3) * ifactor2
+ blu_sca = ((sp2 & b_mask) << 3) * ifactor2
+
+ if blendmode == 'screen':
+ red_blend = red_sca + red_dca - (red_sca * red_dca // 65536)
+ grn_blend = grn_sca + grn_dca - (grn_sca * grn_dca // 65536)
+ blu_blend = blu_sca + blu_dca - (blu_sca * blu_dca // 65536)
+ else:
+ red_blend = red_sca + red_dca * (256 - ifactor2) // 256
+ grn_blend = grn_sca + grn_dca * (256 - ifactor2) // 256
+ blu_blend = blu_sca + blu_dca * (256 - ifactor2) // 256
+
+ r = ((red_blend // ifactor_blend) << 8) & r_mask
+ g = ((grn_blend // ifactor_blend) << 3) & g_mask
+ b = ((blu_blend // ifactor_blend) >> 3) & b_mask
+
+ pixel = (r & r_mask) | (g & g_mask) | (b & b_mask)
+
+ if swap:
+ pixel = ((pixel & 0xFF) << 8) | ((pixel >> 8) & 0xFF)
+
+ elif blend_source1:
+ r = ((sp1 & r_mask) * ifactor1 // 256) & r_mask
+ g = ((sp1 & g_mask) * ifactor1 // 256) & g_mask
+ b = ((sp1 & b_mask) * ifactor1 // 256) & b_mask
+ pixel = r | g | b
+ elif blend_source2:
+ r = ((sp2 & r_mask) * ifactor2 // 256) & r_mask
+ g = ((sp2 & g_mask) * ifactor2 // 256) & g_mask
+ b = ((sp2 & b_mask) * ifactor2 // 256) & b_mask
+ pixel = r | g | b
+ else:
+ pixel = dest[x, y]
+
+ dest[x, y] = pixel