flightgear/test_suite/attic/test-env-map.cxx
2022-10-20 20:29:11 +08:00

275 lines
7.4 KiB
C++

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#ifdef HAVE_WINDOWS_H
# include <windows.h>
#endif
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <simgear/compiler.h>
#if defined( __APPLE__)
# include <OpenGL/OpenGL.h>
# include <GLUT/glut.h>
#else
# include <GL/gl.h>
# ifdef HAVE_GLUT_H
# include <GL/glut.h>
# endif
#endif
#define TEXRES_X 256
#define TEXRES_Y 256
#ifdef HAVE_GLUT_H
unsigned char env_map[TEXRES_X][TEXRES_Y][4];
GLuint texName;
int window_x = 640, window_y = 480;
float alpha = 0.0, beta = 0.0;
/*****************************************************************/
/*****************************************************************/
/*****************************************************************/
void setColor(float x, float y, float z, float angular_size, float r, float g, float b, float a)
{
//normalize
float inv_length = 1.0 / sqrt(x*x + y*y + z*z);
x *= inv_length; y *= inv_length; z *= inv_length;
printf("x = %f, y = %f, z = %f\n", x, y, z);
float cos_angular_size = cos(angular_size*3.1415/180.0);
printf("cos_angular_size = %f\n", cos_angular_size);
for(float tz_sign = -1.0; tz_sign < 3.0; tz_sign += 2.0)
{
for(float tx = -1.0; tx <= 1.0; tx += 0.01)
{
for(float ty = -1.0; ty <= 1.0; ty += 0.01)
{
if ((1.0 - tx*tx - ty*ty)<0.0)
continue;
float tz = tz_sign * sqrt(1.0 - tx*tx - ty*ty);
float cos_phi = x*tx + y*ty + z*tz;
if (cos_angular_size < cos_phi)
{
float rx = tx; //mirroring on the z=0 plane
float ry = ty;
float rz = -tz;
float inv_m = 1.0 / (2.0 * sqrt(rx*rx + ry*ry + (rz + 1)*(rz + 1)));
int s = (int)(TEXRES_X * (rx * inv_m + 0.5));
int t = (int)(TEXRES_Y * (ry * inv_m + 0.5));
//seg_fault protection:
if (s<0) s=0;
if (s>=TEXRES_X) s=TEXRES_X-1;
if (t<0) t=0;
if (t>=TEXRES_Y) t=TEXRES_Y-1;
env_map[s][t][0] = (unsigned char)(r * 255);
env_map[s][t][1] = (unsigned char)(g * 255);
env_map[s][t][2] = (unsigned char)(b * 255);
env_map[s][t][3] = (unsigned char)(a * 255);
}
}
}
}
}
/*****************************************************************/
/*****************************************************************/
/*****************************************************************/
void init(void)
{
glClearColor(0.0, 0.0, 0.0, 0.0);
glShadeModel(GL_FLAT);
glEnable(GL_DEPTH_TEST);
for(int x=0; x<TEXRES_X; x++)
{
for(int y=0; y<TEXRES_Y; y++)
{
env_map[x][y][0] = x; //a few colors
env_map[x][y][1] = y;
env_map[x][y][2] = 128;
env_map[x][y][3] = 128;
}
}
/*****************************************************************/
/*****************************************************************/
/*****************************************************************/
// x y z ang r g b a
setColor(0.0, 0.0, -1.0 , 23.0, 1.0, 1.0, 1.0, 1.0);
setColor(0.7071067, 0.0, -0.7071067, 23.0, 1.0, 0.0, 0.0, 1.0);
/*****************************************************************/
/*****************************************************************/
/*****************************************************************/
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glGenTextures(1, &texName);
glBindTexture(GL_TEXTURE_2D, texName);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, TEXRES_X, TEXRES_Y, 0, GL_RGBA, GL_UNSIGNED_BYTE, env_map);
}
void reshape(int w, int h)
{
window_x = w; window_y = h;
glViewport(0, 0, (GLsizei) w, (GLsizei) h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective((GLdouble) 60.0, ((GLdouble)w)/((GLdouble)h), (GLdouble) 10.0, (GLdouble) 1000.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(0.0, 0.0, -20.0);
}
void display()
{
glClear ( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ) ;
//show light
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective((GLdouble) 60.0, (float)window_x/window_y, (GLdouble) 1.0, (GLdouble) 100.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(0.0, 0.0, -10.0);
glRotatef(alpha, 1.0, 0.0, 0.0);
glRotatef(beta, 0.0, 1.0, 0.0);
glBegin(GL_LINES);
glColor3f(1.0, 1.0, 1.0);
glVertex3f(0.0, 0.0, 0.0);
glVertex3f(0.0, 0.0, 1.0);
glEnd();
/*****************************************************************/
/*****************************************************************/
/*****************************************************************/
glEnable(GL_TEXTURE_2D);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glBindTexture(GL_TEXTURE_2D, texName);
glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);
glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);
glEnable(GL_TEXTURE_GEN_S);
glEnable(GL_TEXTURE_GEN_T);
glBegin(GL_QUADS);
glNormal3f(0.0, 0.0, 1.0);
glVertex3f(1.0, 1.0, 0.0);
glVertex3f(-1.0, 1.0, 0.0);
glVertex3f(-1.0, -1.0, 0.0);
glVertex3f(1.0, -1.0, 0.0);
glEnd();
/*
glPointSize(48.0);
glBegin(GL_POINTS);
glNormal3f(0.0, 0.0, 1.0);
glVertex3f(0.0, 0.0, 0.0);
glEnd();
*/
glDisable(GL_TEXTURE_GEN_S);
glDisable(GL_TEXTURE_GEN_T);
glDisable(GL_TEXTURE_2D);
/*****************************************************************/
/*****************************************************************/
/*****************************************************************/
//show how the map looks like
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
//gluOrtho2D(0.0 -10.0, 1.0 +10.0, -(float)window_x/window_y -10.0,0.0 +10.0);
//glOrtho(0.0, 5.0, -5.0, 0.0, -10.0, 10.0);
glOrtho(0.0, 5.0*((float)window_x/window_y), -5.0, 0.0, -10.0, 10.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glEnable(GL_TEXTURE_2D);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glBindTexture(GL_TEXTURE_2D, texName);
glBegin(GL_QUADS);
glTexCoord2f(0.0, 0.0); glVertex3f(0.0, 0.0, 0.0);
glTexCoord2f(0.0, 1.0); glVertex3f(0.0, -1.0, 0.0);
glTexCoord2f(1.0, 1.0); glVertex3f(1.0, -1.0, 0.0);
glTexCoord2f(1.0, 0.0); glVertex3f(1.0, 0.0, 0.0);
glEnd();
glFlush();
glDisable(GL_TEXTURE_2D);
glutPostRedisplay () ;
glutSwapBuffers () ;
}
void keyboard (unsigned char key, int x, int y)
{
switch(key)
{
case 27:
exit(0);
case '8':
alpha += 1.0;
if (alpha >= 360.0) alpha -= 360.0;
break;
case '2':
alpha -= 1.0;
if (alpha < 0.0) alpha += 360.0;
break;
case '4':
beta -= 1.0;
if (beta <= -90.0) beta = -90.0;
break;
case '6':
beta += 1.0;
if (beta >= 90.0) beta = 90.0;
break;
case '5':
alpha = 0.0; beta = 0.0;
break;
}
}
#endif /* HAVE_GLUT_H */
int main(int argc, char** argv)
{
#ifdef HAVE_GLUT_H
glutInitWindowSize(window_x, window_y);
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
glutCreateWindow(argv[0]);
init();
glutDisplayFunc(display);
glutReshapeFunc(reshape);
glutKeyboardFunc(keyboard);
glutMainLoop();
#else
printf("GL Utility Toolkit (glut) was not found on this system.\n");
#endif
return 0;
}