/* gltest.c */

#include <stdlib.h>
#include "SDL.h"
#include "i2c.h"

#include "SDL_opengl.h"

static void setup_opengl( int width, int height )
{
    float ratio = (float) width / (float) height;

    glShadeModel( GL_SMOOTH );

    glCullFace( GL_BACK );
    glFrontFace( GL_CCW );
    glEnable( GL_CULL_FACE );

    glClearColor( 0, 0, 0, 0 );

    glViewport( 0, 0, width, height );

    glMatrixMode( GL_PROJECTION );
    glLoadIdentity( );

    gluPerspective( 60.0, ratio, 1.0, 1024.0 );
}


void drawscene(int r, int p, int y)
{
    static float roll, pitch, yaw;

    roll  += (float)r / 1000;
    pitch += (float)p / 1000;
    yaw   += (float)y / 1000;

    if (roll > 360.0)
	roll -= 360.0;
    if (roll < 360.0)
	roll += 360.0;
    if (pitch > 360.0)
	pitch -= 360.0;
    if (pitch < 360.0)
	pitch += 360.0;
    if (yaw > 360.0)
	yaw -= 360.0;
    if (yaw < 360.0)
	yaw += 360.0;


    static GLfloat v0[] = { -1.0f, -1.0f,  1.0f };
    static GLfloat v1[] = {  1.0f, -1.0f,  1.0f };
    static GLfloat v2[] = {  1.0f,  1.0f,  1.0f };
    static GLfloat v3[] = { -1.0f,  1.0f,  1.0f };
    static GLfloat v4[] = { -1.0f, -1.0f, -1.0f };
    static GLfloat v5[] = {  1.0f, -1.0f, -1.0f };
    static GLfloat v6[] = {  1.0f,  1.0f, -1.0f };
    static GLfloat v7[] = { -1.0f,  1.0f, -1.0f };
    static GLubyte red[]    = { 255,   0,   0, 255 };
    static GLubyte green[]  = {   0, 255,   0, 255 };
    static GLubyte blue[]   = {   0,   0, 255, 255 };
    static GLubyte white[]  = { 255, 255, 255, 255 };
    static GLubyte yellow[] = {   0, 255, 255, 255 };
    static GLubyte black[]  = {   0,   0,   0, 255 };
    static GLubyte orange[] = { 255, 255,   0, 255 };
    static GLubyte purple[] = { 255,   0, 255,   0 };

    glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );

    /* We don't want to modify the projection matrix. */
    glMatrixMode( GL_MODELVIEW );
    glLoadIdentity( );

    /* Move down the z-axis. */
    glTranslatef( (float)0*4, (float)0*4, -5.0 );

    /* Apply rotation from our model */
    glRotatef( roll,  1.0, 0.0, 0.0 );
    glRotatef( pitch, 0.0, 0.0, 1.0 );
    glRotatef( yaw,   0.0, -1.0, 0.0 );

    /* Send our triangle data to the pipeline. */
    glBegin( GL_TRIANGLES );

    glColor4ubv( red );
    glVertex3fv( v0 );
    glColor4ubv( green );
    glVertex3fv( v1 );
    glColor4ubv( blue );
    glVertex3fv( v2 );

    glColor4ubv( red );
    glVertex3fv( v0 );
    glColor4ubv( blue );
    glVertex3fv( v2 );
    glColor4ubv( white );
    glVertex3fv( v3 );

    glColor4ubv( green );
    glVertex3fv( v1 );
    glColor4ubv( black );
    glVertex3fv( v5 );
    glColor4ubv( orange );
    glVertex3fv( v6 );

    glColor4ubv( green );
    glVertex3fv( v1 );
    glColor4ubv( orange );
    glVertex3fv( v6 );
    glColor4ubv( blue );
    glVertex3fv( v2 );

    glColor4ubv( black );
    glVertex3fv( v5 );
    glColor4ubv( yellow );
    glVertex3fv( v4 );
    glColor4ubv( purple );
    glVertex3fv( v7 );

    glColor4ubv( black );
    glVertex3fv( v5 );
    glColor4ubv( purple );
    glVertex3fv( v7 );
    glColor4ubv( orange );
    glVertex3fv( v6 );

    glColor4ubv( yellow );
    glVertex3fv( v4 );
    glColor4ubv( red );
    glVertex3fv( v0 );
    glColor4ubv( white );
    glVertex3fv( v3 );

    glColor4ubv( yellow );
    glVertex3fv( v4 );
    glColor4ubv( white );
    glVertex3fv( v3 );
    glColor4ubv( purple );
    glVertex3fv( v7 );

    glColor4ubv( white );
    glVertex3fv( v3 );
    glColor4ubv( blue );
    glVertex3fv( v2 );
    glColor4ubv( orange );
    glVertex3fv( v6 );

    glColor4ubv( white );
    glVertex3fv( v3 );
    glColor4ubv( orange );
    glVertex3fv( v6 );
    glColor4ubv( purple );
    glVertex3fv( v7 );

    glColor4ubv( green );
    glVertex3fv( v1 );
    glColor4ubv( red );
    glVertex3fv( v0 );
    glColor4ubv( yellow );
    glVertex3fv( v4 );

    glColor4ubv( green );
    glVertex3fv( v1 );
    glColor4ubv( yellow );
    glVertex3fv( v4 );
    glColor4ubv( black );
    glVertex3fv( v5 );

    glEnd( );

    SDL_GL_SwapBuffers();
}

int main(int argc, char *argv[])
{
    SDL_Surface *screen;
    int roll, pitch, yaw;

    if ( SDL_Init(SDL_INIT_AUDIO|SDL_INIT_VIDEO) < 0 ) {
        fprintf(stderr, "Unable to init SDL: %s\n", SDL_GetError());
        exit(1);
    }
    atexit(SDL_Quit);

    SDL_GL_SetAttribute( SDL_GL_RED_SIZE, 8 );
    SDL_GL_SetAttribute( SDL_GL_GREEN_SIZE, 8 );
    SDL_GL_SetAttribute( SDL_GL_BLUE_SIZE, 8 );
    SDL_GL_SetAttribute( SDL_GL_DEPTH_SIZE, 32 );
    SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 );

    //screen = SDL_SetVideoMode(640, 480, 32, SDL_HWSURFACE);
    screen = SDL_SetVideoMode(640, 480, 32, SDL_OPENGL);
    if ( screen == NULL ) {
        fprintf(stderr, "Unable to set 640x480 video: %s\n", SDL_GetError());
        exit(1);
    }

    setup_opengl(640, 480);

    initparallel();
    setupi2c();
    calibrate();

    query_device(&roll, &pitch, &yaw);
    drawscene(roll, pitch, yaw);

    while (1)
    {
	SDL_Event event;
/*	SDL_WaitEvent(&event); */
	while (SDL_PollEvent(&event))
	{
	    switch (event.type)
	    {
	        case SDL_QUIT:
		case SDL_KEYDOWN:
		    exit(0);
	    }
	}
	query_device(&roll, &pitch, &yaw);
        drawscene(roll, pitch, yaw);
    }
	
}