For cross platform windowing, input, font rendering and probably the entire 2d gui render of the engine, I have decided to use PySDL2, since I had some troubles with SFML (crashes in debug mode in PyCharm).
Next is an almost direct conversion from C to Python of the example found here:
http://www.willusher.io/sdl2%20tutorials/2013/12/18/lesson-6-true-type-fonts-with-sdl_ttf/
The Glametrix font I used comes from here:
http://www.glukfonts.pl/font.php?font=Glametrix
I placed the SDL2 and SDL2_ttf libraries in the script’s folder, inside another folder called ‘libs’ and the font in a folder called ‘font’.
Result:
Code:
import os
from sys import exit
from ctypes import c_long, pointer
sdlpath = os.path.join(os.path.dirname(__file__), 'libs')
os.environ['PYSDL2_DLL_PATH'] = sdlpath
from sdl2 import *
from sdl2.sdlttf import *
def renderTexture(tex, ren, x, y):
"""
:type ren: SDL_Renderer
:type tex: SDL_Texture
"""
#Setup the destination rectangle to be at the position we want
dst = SDL_Rect(x, y)
w = pointer(c_long(0))
h = pointer(c_long(0))
#Query the texture to get its width and height to use
SDL_QueryTexture(tex, None, None, w, h)
dst.w = w.contents.value
dst.h = h.contents.value
SDL_RenderCopy(ren, tex, None, dst)
def renderText(message, fontFile, color, fontSize, renderer):
"""
:rtype : SDL_Texture
"""
# Open the font
SDL_ClearError()
font = TTF_OpenFont(fontFile, fontSize)
p = SDL_GetError()
if font is None or not p == '':
print("TTF_OpenFont error: " + p)
return None
#We need to first render to a surface as that's what TTF_RenderText
#returns, then load that surface into a texture
surf = TTF_RenderText_Blended(font, message, color)
if surf is None:
TTF_CloseFont(font)
print("TTF_RenderText")
return None
texture = SDL_CreateTextureFromSurface(renderer, surf)
if texture is None:
print("CreateTexture")
#Clean up the surface and font
SDL_FreeSurface(surf)
TTF_CloseFont(font)
return texture
SDL_Init(SDL_INIT_VIDEO)
#Create an application window with the following settings:
window = SDL_CreateWindow(
"SDL2 TTF test", # window title
SDL_WINDOWPOS_CENTERED, # initial x position
SDL_WINDOWPOS_CENTERED, # initial y position
640, # width, in pixels
480, # height, in pixels
SDL_WINDOW_RESIZABLE # flags
)
renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED)
tfi = TTF_Init()
if tfi != 0:
print("TTF_Init")
exit(1)
#We'll render the string "TTF fonts are cool!" in white
#Color is in RGB format
color = SDL_Color(255, 255, 255)
fontpath = os.path.join(os.path.dirname(__file__), 'font', 'Glametrix.otf')
image = renderText("TTF fonts are cool!", fontpath,
color, 64, renderer)
if image is None:
exit(1)
#Getting the window size.
SCREEN_WIDTH = pointer(c_long(0))
SCREEN_HEIGHT = pointer(c_long(0))
SDL_GetWindowSize(window, SCREEN_WIDTH, SCREEN_HEIGHT)
#Get the texture w/h so we can center it in the screen
iW = pointer(c_long(0))
iH = pointer(c_long(0))
SDL_QueryTexture(image, None, None, iW, iH)
x = SCREEN_WIDTH.contents.value / 2 - iW.contents.value / 2
y = SCREEN_HEIGHT.contents.value / 2 - iH.contents.value / 2
r = 1
event = SDL_Event()
while r:
if SDL_PollEvent(event):
if event.type == SDL_QUIT:
r = 0
elif event.type == SDL_WINDOWEVENT:
if event.window.event == SDL_WINDOWEVENT_RESIZED:
SDL_GetWindowSize(window, SCREEN_WIDTH, SCREEN_HEIGHT)
x = SCREEN_WIDTH.contents.value / 2 - iW.contents.value / 2
y = SCREEN_HEIGHT.contents.value / 2 - iH.contents.value / 2
if r:
SDL_RenderClear(renderer)
#We can draw our message as we do any other texture, since it's been
#rendered to a texture
renderTexture(image, renderer, x, y)
SDL_RenderPresent(renderer)
SDL_DestroyTexture(image)
SDL_DestroyRenderer(renderer)
SDL_DestroyWindow(window)
SDL_Quit()
I moved the drawing stuff to the event processing so the text is drawn only if there is a change (window re-paint, resize).
PS: Somebody knows a way to avoid using ctypes pointers in the few PySDL2 functions that need them?
egDev 