GLdc/GL/glu.c
2025-03-31 21:08:53 +11:00

32 lines
1.1 KiB
C

#include <math.h>
#include "private.h"
/* Set the Perspective */
void APIENTRY gluPerspective(GLdouble angle, GLdouble aspect,
GLdouble znear, GLdouble zfar) {
GLdouble fW, fH;
fH = tan(angle * (M_PI / 360.0)) * znear;
fW = fH * aspect;
glFrustum(-fW, fW, -fH, fH, znear, zfar);
}
void APIENTRY gluOrtho2D(GLdouble left, GLdouble right, GLdouble bottom, GLdouble top) {
glOrtho(left, right, bottom, top, -1.0f, 1.0f);
}
/* generate mipmaps for any image provided by the user and then pass them to OpenGL */
GLint APIENTRY gluBuild2DMipmaps(GLenum target, GLint internalFormat,
GLsizei width, GLsizei height,
GLenum format, GLenum type, const void *data){
/* 2d texture, level of detail 0 (normal), 3 components (red, green, blue),
width & height of the image, border 0 (normal), rgb color data,
unsigned byte data, and finally the data itself. */
glTexImage2D(GL_TEXTURE_2D, 0, 3, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data);
glGenerateMipmap(GL_TEXTURE_2D);
// FIXME return glu error codes
return 0;
}