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/*
* render-text.c
*
* Simple text rendering
*
* (c) 2008 Thomas White <taw27@cam.ac.uk>
*
* thrust3d - a silly game
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <png.h>
#include <stdlib.h>
#include <glew.h>
#include "render.h"
#include "texture.h"
void render_text_setup(RenderContext *r) {
texture_load(r, "font");
}
void render_text_write(GLfloat x, GLfloat y, const char *text, RenderContext *r) {
Texture *texture;
int i;
const GLfloat lwidth = 0.03;
const GLfloat lheight = lwidth*r->aspect;
const GLfloat lspacing = lwidth/10.0;
y -= lheight;
texture = texture_lookup(r, "font");
glBindTexture(GL_TEXTURE_2D, texture->texname);
glEnable(GL_TEXTURE_2D);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glBegin(GL_QUADS);
for ( i=0; i<strlen(text); i++ ) {
int idx;
int tx, ty;
GLfloat txc, tyc;
const GLfloat unit = 1.0/8.0;
char c;
c = text[i];
if ( c == ' ' ) {
x += lwidth + lspacing;
continue;
}
if ( c == '-' ) {
c = 'Z' + 1;
}
if ( (c == '\r') || (c == '\n') ) {
continue;
}
idx = toupper(c) - 'A';
tx = idx % 8; ty = idx / 8;
txc = tx * unit;
tyc = (1.0-unit) - ty * unit;
glColor3f(0.4, 0.4, 0.4);
glTexCoord2f(txc, tyc);
glVertex2f(x, y);
glTexCoord2f(txc+unit, tyc);
glVertex2f(x+lwidth, y);
glColor3f(0.8, 0.8, 0.8);
glTexCoord2f(txc+unit, tyc+unit);
glVertex2f(x+lwidth, y+lheight);
glTexCoord2f(txc, tyc+unit);
glVertex2f(x, y+lheight);
x += lwidth + lspacing;
}
glEnd();
glDisable(GL_TEXTURE_2D);
}
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