font.py

import pygame #import all of pygame
from pygame.locals import *

import settings #load settings
import data

#class for managing a font
class Font:
    def __init__(self, file):
        self.letters = {} #dictionary of letters
        
        font_dom = data.load_xml(file).documentElement #load and parse font
        image_file = font_dom.getAttribute("image") #get font bitmap file name
        self.image = data.load_image(image_file) #load font bitmap
        self.image.convert_alpha() #convert it to draw faster
        self.height = int(font_dom.getAttribute("height")) #get height of characters
        self.id = font_dom.getAttribute("id") #get font ID
        
        #load all the letters
        for letter in font_dom.getElementsByTagName("letter"):
            name = letter.getAttribute("name") #get name of letter
            width = int(letter.getAttribute("size")) #get width of letter
            coords = letter.getAttribute("coord").split(",") #get coordinate of letter
            #make a rect of the letter bitmap
            rect = pygame.Rect(int(coords[0].strip()), int(coords[1].strip()), \
                width, self.height)
            self.letters[name] = rect #store the letter
    #build a list of letter rects from a string
    def get_letters(self, str):
        letter_rects = []
        code = None
        for letter in str: #loop through all the letters in the string
            if letter == "{" and code is None: #if it's the start of a code
                code = "" #clear out the code
                continue #go to next letter
            if letter == "}" and code is not None: #if it's the end of a code
                if code not in self.letters: #if we don't know what it is
                    code = None #clear code
                    continue #go to next letter
                letter_rects.append(self.letters[code]) #save rect
                code = None #clear code
                continue #go to next letter
            if letter not in self.letters: #if we don't know what it is
                continue #go to next letter
            if code is not None: #if we're in a code
                code += letter #add a letter to the code
            else: #if we're not
                letter_rects.append(self.letters[letter]) #add the letter rect
        return letter_rects #return result
    #get the width of a string
    def get_width(self, str):
        rects = self.get_letters(str) #get the list of rectangles
        total = 0 #total width
        for letter in rects: #loop through all the rects
            total += letter.width #add the widths together
        return total #return the total width
    #render a string
    def render(self, str, dest, where):
        rects = self.get_letters(str) #get the letter rects
        x = 0 #current X position
        for letter in rects: #loop through them
            #render a letter
            dest.blit(self.image, (where[0]+x, where[1]), letter)
            x += letter.width #go to the position of the next letter
        return x #return the width of the rendered string