Initial commit.

Author: halcy

AnsiGraphics.py

@@ -0,0 +1,85 @@
+import numpy as np
+
+class AnsiGraphics:
+    """
+    This class manages ansi fonts and colours.
+    """
+    
+    # VGA Palette
+    VGA_PAL = [
+        np.array([0, 0, 0]) / 255.0,
+        np.array([170, 0, 0]) / 255.0,
+        np.array([0, 170, 0]) / 255.0,
+        np.array([170, 85, 0]) / 255.0,
+        np.array([0, 0, 170]) / 255.0,
+        np.array([170, 0, 170]) / 255.0,
+        np.array([0, 170, 170]) / 255.0,
+        np.array([170, 170, 170]) / 255.0,
+        np.array([85, 85, 85]) / 255.0,
+        np.array([255, 85, 85]) / 255.0,
+        np.array([85, 255, 85]) / 255.0,
+        np.array([255, 255, 85]) / 255.0,
+        np.array([85, 85, 255]) / 255.0,
+        np.array([255, 85, 255]) / 255.0,
+        np.array([85, 255, 255]) / 255.0,
+        np.array([255, 255, 255]) / 255.0
+    ];
+    
+    def __init__(self, font_file):
+        """
+        Reads the font to use and prepares it for usage.
+        Fonts are files with a sequence of bits specifying 8x16 characters.
+        """
+        # Read the font
+        f = open("vga.fnt", "rb")
+        in_bits = []
+        try:
+            byte = f.read(1)
+            while len(byte) != 0:
+                bin_str = bin(int.from_bytes(byte, 'little'))[2:]
+                for bit in bin_str.zfill(8):
+                    in_bits.append(bit)
+                byte = f.read(1)
+        finally:
+            f.close()
+        
+        # Split into chars
+        self.font_chars = []
+        for i in range(0, 256):
+            char_bits = np.array(in_bits[i * 16 * 8 : (i + 1) * 16 * 8])
+            char_bits = char_bits.reshape(16, 8).astype(float)
+            self.font_chars.append(char_bits)
+            
+        # It's 2018 and memory is cheap, so lets precompute every possible fore/back/char combination
+        self.colour_chars = []
+        for char_idx in range(0, 256):
+            fg_chars = []
+            for fg_idx in range(0, 16):
+                bg_chars = []
+                for bg_idx in range(0, 16):
+                    char_base = self.font_chars[char_idx][:]
+                    char_col = np.zeros((char_base.shape[0], char_base.shape[1], 3))
+                    char_col[np.where(char_base == 1)] = AnsiGraphics.VGA_PAL[fg_idx]
+                    char_col[np.where(char_base == 0)] = AnsiGraphics.VGA_PAL[bg_idx]
+                    bg_chars.append(char_col)
+                fg_chars.append(bg_chars)
+            self.colour_chars.append(fg_chars)
+            
+    def vga_colour(self, pal_idx):
+        """
+        Returns the VGA palette colour with the given index as an RGP triplet.
+        """
+        return AnsiGraphics.VGA_PAL[idx]
+    
+    def char_bitmap(self, char_idx):
+        """
+        Returns the font character with the given index as a binary bitmap.
+        """
+        return self.font_chars[idx]
+    
+    def coloured_char(self, char_idx, fg_idx, bg_idx):
+        """
+        Returns the font character with the given index and given fore and back colours as an RGP bitmap.
+        """
+        return self.colour_chars[char_idx][fg_idx][bg_idx]
+