On 3/26/2014 6:51 PM, "Róbert László Páli" wrote:
I am programming a new GUI widget library based on OpenGL for D.
For that I manually bind the used OpenGL functions to D and create
an abstraction layer to draw things, boxes, texts, shapes, etc.
http://palaes.rudanium.org/HueApp/intro.php
The thing compiles nicely with SDL, FreeType, FTGL. But
for the text drawing I use some pretty lame binding currently.
It is a fresh part of the code and want to do it properly:
C Code:
unsigned long loadFont(char * path) {
FTGLfont * font = FTGLloadFont(path);
return (unsigned long) font;
}
void drawText(unsigned long font, unsigned size, char * text) {
// do the text drawing here
}
void destroyFont(unsigned long font) {
FTGLdestroyFont((FTGLfont * ) font);
}
D Code:
extern (C) ulong loadFont(char * path);
extern (C) void destroyFont(ulong font);
void main() {
// init screen and OpenGL setup
auto font = loadFont(cast (char * ) "Arial.TTF");
scope (exit) destroyFont(font);
// draw some text
// close OpenGL and SDL with some second delay
}
This works properly, and long is surely large enough to hold
a pointer in it, I could use sizet, I know that would be better.
A big gaping hole here is that longs in C can be 32-bit or 64-bit
depending on the compiler and platform. Any time you want to bind to
anything using longs in C, you should import core.stdc.config and use
the c_long and c_ulong types.
