main.c

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/* Copyright (C) Gabor Nagy, 2000. 
 * All rights reserved worldwide.
 *
 * This software is provided "as is" without express or implied
 * warranties. You may freely copy and compile this source into
 * applications you distribute provided that the copyright text
 * below is included in the resulting source code, for example:
 * "Portions Copyright (C) Gabor Nagy, 2000"
 */
/*==============================================================================*/
/* Real-time glass								*/
/*										*/
/* - The Main									*/
/*										*/
/* AUTHOR:	Gabor Nagy							*/
/* DATE:	2000-May-02 14:49:29						*/
/*  v1.0									*/
/*										*/
/* For Game Programming Graphics Gems						*/
/*==============================================================================*/
#include <stdio.h>
#include <math.h>
#include <GL/glut.h>
#include <stdlib.h>
#ifdef _WIN32
#include <windows.h>
#include <time.h>
#else
#include <sys/time.h>
#include <sys/param.h>
#endif

#include "str.h"
#include "obj.h"

E3dModel*	Scn_GlassModel=NULL;
E3dModel*	Scn_BulbGlassModel=NULL;
E3dModel*	Scn_BulbBlackModel=NULL;
E3dModel*	Scn_BulbCopperModel=NULL;
E3dModel*	Scn_ClothModel=NULL;
E3dModel*	Scn_TableModel=NULL;

E3dLight	Sh_Light;

enum
{
 ShDOLLY_CAMERA=0, ShMOVE_LIGHT
};


int	Sh_MiddleMouseMode=ShDOLLY_CAMERA;

int	Sh_DisplayMode=0;

#ifdef _WIN32
float			Sh_StartTime;
#else
unsigned long	Sh_StartTime;
#endif
unsigned long	Sh_Frame=0;
unsigned long	Sh_NumOfFrames=200;

// Shadow map
//
unsigned long*	Sh_ShadowMapImage=NULL;
int		Sh_ShadowMapXSize=128,Sh_ShadowMapYSize=128;


int		Sh_TexXSize, Sh_TexYSize;
GLubyte*	Sh_TexImage;
GLuint		Sh_EnvMapTexId, Sh_WoodTexId;

float		Scn_CameraX=0.0, Scn_CameraY=0.0, Scn_CameraZ=0.0;

E3dLight	Scn_Headlight;


// Viewing
//
float	Sh_Longitude=152.0, Sh_Latitude=-36.0;
float	Sh_ViewDistance = 20.0;
float	Sh_ZNear=0.1, Sh_ZFar=8192.0;
float	Sh_WindowAspect = 4.0/3.0;
long	Sh_WindowXSize, Sh_WindowYSize;
int	Sh_PrevMX, Sh_PrevMY;
EBool	Sh_LeftButton = FALSE, Sh_MiddleButton = FALSE;

int	Sh_MainMenu, Sh_DisplayMenu;

int	Sh_CurrentGlassObject=-1;


/*======================================*/
/* Setlect blocker object		*/
/*======================================*/
void ShCB_SetlectGlassObject(int LValue)
{
 E3dModel*	LModel;
 E3dMesh*	LMesh;
 E3dPolyGroup*	LPolyGroup;
 E3dMaterial*	LMaterial;

 if(Sh_CurrentGlassObject!=LValue)
 {
   switch(LValue) 
   {
     case 0: 
       if(Scn_GlassModel!=NULL) E3d_ModelFree(Scn_GlassModel);
       if((LModel=E3d_ReadOBJFile("objects/BulbGlass.obj")) != NULL)
       {
	 Scn_GlassModel = LModel;

	 if((LMesh=(E3dMesh*)(LModel->Geometry))!=NULL)
	 {
	   LPolyGroup=LMesh->PolyGroups[0];
	   LPolyGroup->Material=LMaterial=E3d_MaterialAllocate();
	   LMaterial->Ambient[0]=0.0;
	   LMaterial->Ambient[1]=0.0;
	   LMaterial->Ambient[2]=0.0;

	   LMaterial->Diffuse[0]=3.0;LMaterial->Diffuse[1]=3.0;LMaterial->Diffuse[2]=3.0;LMaterial->Diffuse[3]=0.36;
	 }
       }

       if((LModel=E3d_ReadOBJFile("objects/BulbBlack.obj")) != NULL)
       {
         Scn_BulbBlackModel = LModel;
// Plastic part of light bulb
//
	 if((LMesh=(E3dMesh*)(LModel->Geometry))!=NULL)
	 {
	   LPolyGroup=LMesh->PolyGroups[0];
	   LPolyGroup->Material=LMaterial=E3d_MaterialAllocate();
	   LMaterial->Ambient[0]=0.0;
	   LMaterial->Ambient[1]=0.0;
	   LMaterial->Ambient[2]=0.0;
	   LMaterial->Diffuse[0]=0.1;
	   LMaterial->Diffuse[1]=0.1;
	   LMaterial->Diffuse[2]=0.1;
	 }

	 E3d_ModelRefreshMatrices(LModel);
       }

       if((LModel=E3d_ReadOBJFile("objects/BulbCopper.obj")) != NULL)
       {
         Scn_BulbCopperModel = LModel;
// Copper part of light bulb
//
	 if((LMesh=(E3dMesh*)(LModel->Geometry))!=NULL)
	 {
	   LPolyGroup=LMesh->PolyGroups[0];
	   LPolyGroup->Material=LMaterial=E3d_MaterialAllocate();
	   LMaterial->Ambient[0]=2.0;
	   LMaterial->Ambient[1]=1.2;
	   LMaterial->Ambient[2]=0.4;
	   LMaterial->Diffuse[0]=1.0;
	   LMaterial->Diffuse[1]=0.6;
	   LMaterial->Diffuse[2]=0.2;
	 }

	 E3d_ModelRefreshMatrices(LModel);
       }
     break;
   }
   Sh_CurrentGlassObject=LValue;
 }

 glutPostRedisplay();
}


/*======================================*/
/* Main menu callback			*/
/*======================================*/
void ShCB_MainMenu(int value)
{
  switch(value) 
  {
    case 5:	exit(0);   break;
  }
}



/*==============================*/
/* Read raw RGBA file		*/
/*==============================*/
char* E3d_LoadImage(char* LFileName)
{
 FILE*		LInFile;
 char*		LBuffer=NULL;
 unsigned long	LFileSize;

 if((LInFile=fopen(LFileName,"r"))!=NULL)
 {

// Determine file length
//
  fseek(LInFile, 0, SEEK_END);

  LFileSize=ftell(LInFile);

  fseek(LInFile, 0, SEEK_SET);

// Allocate buffer and read file
//
  if((LBuffer=EMalloc(LFileSize))!=NULL)
  {
   fread(LBuffer, 1, LFileSize, LInFile);
  }

  fclose(LInFile);
 }

 return(LBuffer);
}


/*==============================*/
/* Initialize textures		*/
/*==============================*/
void Sh_InitTextures(void)
{
 int		LTexXSize, LTexYSize;
 GLubyte*	LTexData;

// Read and set up wood texture
//
 glGenTextures(1,&Sh_WoodTexId);
 glBindTexture(GL_TEXTURE_2D, Sh_WoodTexId);

 if((LTexData=(GLubyte*)E3d_LoadImage("Wood.rgba"))!=NULL)
 {
  LTexXSize=128;LTexYSize=128;

  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  glTexImage2D(GL_TEXTURE_2D, 0, 4, LTexXSize, LTexYSize, 0, GL_RGBA, GL_UNSIGNED_BYTE, LTexData );
 }


// Read and set up environment-map texture
//
 glGenTextures(1,&Sh_EnvMapTexId);
 glBindTexture(GL_TEXTURE_2D, Sh_EnvMapTexId);

 if((LTexData=(GLubyte*)E3d_LoadImage("Envmap.rgba"))!=NULL)
 {
  LTexXSize=128;LTexYSize=128;

  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  glTexImage2D(GL_TEXTURE_2D, 0, 4, LTexXSize, LTexYSize, 0, GL_RGBA, GL_UNSIGNED_BYTE, LTexData );
 }
}


/*==============================*/
/* Render the scene		*/
/*==============================*/
void Sh_DrawScene()
{
 E3dModel*	LModel;
 E3dMesh*	LMesh;
 E3dPolyGroup*	LPolyGroup;
 E3dMaterial*	LMaterial;


 glEnable(GL_LIGHTING);
 glDisable(GL_TEXTURE_2D);

 E3d_GLUpdateLight(0, &Sh_Light);

// Draw cloth
//
 if((LModel=Scn_ClothModel)!=NULL)
 {
  glPushMatrix();

  glDisable(GL_TEXTURE_2D);

  E3d_DrawModel(LModel, FALSE, &Sh_Light, FALSE);
  glPopMatrix();
 }


// Draw table
//
 if((LModel=Scn_TableModel)!=NULL)
 {
  glPushMatrix();

// Set up wood texture
//
  glEnable(GL_TEXTURE_2D);

  glBindTexture(GL_TEXTURE_2D, Sh_WoodTexId);
  glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
  glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR);
  glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_OBJECT_LINEAR);
  glDisable(GL_TEXTURE_GEN_S);
  glDisable(GL_TEXTURE_GEN_T);

  E3d_DrawModel(LModel, TRUE, &Sh_Light, FALSE);
  glPopMatrix();
 }


// Draw light bulb copper part
//
 if((LModel=Scn_BulbCopperModel)!=NULL)
 {
  glPushMatrix();
  glEnable(GL_TEXTURE_2D);

// Set up shpere-map texture
//
  glBindTexture(GL_TEXTURE_2D, Sh_EnvMapTexId);
  glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
  glEnable(GL_TEXTURE_2D);

// Texture-coordinate generation method
//
  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);

  E3d_DrawModel(LModel, FALSE, &Sh_Light, FALSE);
  glPopMatrix();
 }


// Draw light bulb plastic part
//
 if((LModel=Scn_BulbBlackModel)!=NULL)
 {
  glDisable(GL_TEXTURE_2D);
  glPushMatrix();

  E3d_DrawModel(LModel, FALSE, &Sh_Light, FALSE);
  glPopMatrix();
 }


// Render glass model
//
 if(Scn_GlassModel!=NULL)
 {
  glEnable(GL_BLEND);

// Turn off Z update
//