/*****************************************************************
  multitex.cpp
  by Dave Pape
  20 April 2003

*****************************************************************/
#include <stdlib.h>
#include <math.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <GL/glut.h>
#include <GL/gl.h>
#include <dms/dms.h>

using namespace dms;

void createScene(Object& root);
void drawEverything(void);

void key(unsigned char k, int x, int y);
void specialkey(int k, int x, int y);
void idle(void);

PerspCamera camera;
Light light;
Object root;
QuadricObject cylinder;
Texture2D colorTexture("metal_bluecloudycarpaint.sgi");
Texture2D reflectionTexture("flowers.tif");
Texture2D lightTexture("lightcircle.tif", GL_CLAMP);


int main(int argc, char *argv[])
    {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
    glutInitWindowSize(512,512);
    glutCreateWindow(argv[0]);
    
    glutDisplayFunc(drawEverything);
    glutKeyboardFunc(key);
    glutSpecialFunc(specialkey);
    glutIdleFunc(idle);
    
    camera.setPosition(0, 5, 20);
    light.setInfinitePosition(1, 1, 1);
    createScene(root);

    glutMainLoop();
    return 0;
    }


void createScene(Object& root)
    {
    Square * square;
    Material * material;
        
    square = new Square(-50, -50, 50, 50, DMS_Y);
    material = new Material(Color::Green);
    square->setMaterial(*material);
    root.attach(*square);

    cylinder.makeCylinder(3.0, 3.0, 8.0, 64, 1, DMS_Y);
    cylinder.setMaterial(*(new Material(Color::White)));
    cylinder.setTexture(colorTexture);
    cylinder.setUseTexture(GL_TRUE);
    }


void drawEverything(void)
    {
    glClearColor(0, 0, 0, 0.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glEnable(GL_DEPTH_TEST);
    
    camera.apply();
#if 1
    light.apply();
    root.drawAll();
    cylinder.drawAll();
    light.disable();
#endif

    glDepthFunc(GL_EQUAL);
    
#if 1
    glColor4f(1, 1, 1, 0.2);
    reflectionTexture.apply();
    glEnable(GL_TEXTURE_GEN_S);
    glEnable(GL_TEXTURE_GEN_T);
    glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);
    glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);
    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    
// This blending mode is fast on GeForce4, but horribly slow on TNT
//    glBlendFunc(GL_CONSTANT_ALPHA, GL_ONE_MINUS_CONSTANT_ALPHA);
//    glBlendColor(1, 1, 1, 0.2);

    cylinder.draw();
    reflectionTexture.disable();
    glDisable(GL_BLEND);
    glDisable(GL_TEXTURE_GEN_S);
    glDisable(GL_TEXTURE_GEN_T);
#endif

#if 1
    glEnable(GL_BLEND);
    glBlendFunc(GL_ZERO, GL_SRC_COLOR);
    lightTexture.apply();
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
    glEnable(GL_TEXTURE_GEN_S);
    glEnable(GL_TEXTURE_GEN_T);
    glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
    glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
    GLfloat SplaneCoefficients[4] = { 0.1, 0, 0, 0.4 };
    GLfloat TplaneCoefficients[4] = { 0, 0.1, 0, 0.4 };
    glTexGenfv(GL_S, GL_EYE_PLANE, SplaneCoefficients);
    glTexGenfv(GL_T, GL_EYE_PLANE, TplaneCoefficients);
    cylinder.draw();
    lightTexture.disable();
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
    glDisable(GL_TEXTURE_GEN_S);
    glDisable(GL_TEXTURE_GEN_T);
    glDisable(GL_BLEND);
#endif

    glDepthFunc(GL_LESS);

    glutSwapBuffers();
    checkGLError("end-of-frame");
    }


void key(unsigned char k, int x, int y)
    {
    if (k == 27)
        exit(0);
    }


void specialkey(int k, int x, int y)
    {
    if (k == GLUT_KEY_LEFT)
        camera.turn(1);
    else if (k == GLUT_KEY_RIGHT)
        camera.turn(-1);
    else if (k == GLUT_KEY_UP)
        camera.pitch(1);
    else if (k == GLUT_KEY_DOWN)
        camera.pitch(-1);
    else if (k == GLUT_KEY_HOME)
        camera.moveForward(0.25);
    else if (k == GLUT_KEY_END)
        camera.moveForward(-0.25);
    else if (k == GLUT_KEY_PAGE_UP)
        camera.zoom(-1);
    else if (k == GLUT_KEY_PAGE_DOWN)
        camera.zoom(1);
    }


void idle(void)
    {
    root.updateAll();
    glutPostRedisplay();
    }