#ifndef SKYBOX_H_
#define SKYBOX_H_

#pragma once
#include <d3dx9.h>
#include <vector>
#include <string>

class SkyBox
{
public:
   SkyBox();
   ~SkyBox();

   ID3DXMesh* SkyboxMesh;
   IDirect3DTexture9* SkyboxTextures[6];

   void CreateSkyBox( IDirect3DDevice9* D3DDevice );
   void RenderSkybox( IDirect3DDevice9* D3DDevice, D3DXVECTOR3 EyePosition );
};

#endif //SKYBOX_H_

//////////////////////////////////////////////////////////////////////////////////////////////////
// File: SkyBox.cpp
// Author: Chris Smith
// Date Created: 2/22/06
// Description: Holds all of the SkyBox data
// Copyright: Use this however you want, but I am not responsible for anything
//////////////////////////////////////////////////////////////////////////////////////////////////

#include "SkyBox.h"

///////////////////////////////////////////////////////
// SkyBox FVF
///////////////////////////////////////////////////////
struct SkyboxVertex
{
   SkyboxVertex(){}
   SkyboxVertex(float x, float y, float z, float u, float v)
   {
      _x = x;   _y = y;   _z = z;
      _u = u;   _v = v;
   }

   float _x, _y, _z, _u, _v;

   static const DWORD FVF;
};
const DWORD SkyboxVertex::FVF = D3DFVF_XYZ | D3DFVF_TEX1;

///////////////////////////////////////////////////////
// SkyBox Constructor
///////////////////////////////////////////////////////
SkyBox::SkyBox()
{
   SkyboxMesh = 0;
   for(int i = 0; i < 6; i++)
      SkyboxTextures[i] = 0;
}

///////////////////////////////////////////////////////
// SkyBox Deconstructor
///////////////////////////////////////////////////////
SkyBox::~SkyBox()
{
   SkyboxMesh->Release(); SkyboxMesh = NULL;
   for(int i = 0; i < 6; i++)
      SkyboxTextures[i]->Release();
};

///////////////////////////////////////////////////////
// Create the SkyBox
///////////////////////////////////////////////////////
void SkyBox::CreateSkyBox( IDirect3DDevice9* D3DDevice )
{
   //Create the skybox SkyboxMesh
   D3DXCreateMeshFVF(
   12,
   24,
   D3DXMESH_MANAGED,
   SkyboxVertex::FVF,
   D3DDevice,
   &SkyboxMesh);

   // Fill the verticies
   SkyboxVertex* v = 0;
   SkyboxMesh->LockVertexBuffer(0, (void**)&v);

   v[0] = SkyboxVertex( 1.0f, -1.0f,  1.0f, 0.0f, 1.0f);
   v[1] = SkyboxVertex( 1.0f,  1.0f,  1.0f, 0.0f, 0.0f);
   v[2] = SkyboxVertex( 1.0f,  1.0f, -1.0f, 1.0f, 0.0f);
   v[3] = SkyboxVertex( 1.0f, -1.0f, -1.0f, 1.0f, 1.0f);

   v[4] = SkyboxVertex(-1.0f, -1.0f, -1.0f, 0.0f, 1.0f);
   v[5] = SkyboxVertex(-1.0f,  1.0f, -1.0f, 0.0f, 0.0f);
   v[6] = SkyboxVertex(-1.0f,  1.0f,  1.0f, 1.0f, 0.0f);
   v[7] = SkyboxVertex(-1.0f, -1.0f,  1.0f, 1.0f, 1.0f);

   v[8]  = SkyboxVertex(-1.0f,  1.0f,  1.0f, 0.0f, 1.0f);
   v[9]  = SkyboxVertex(-1.0f,  1.0f, -1.0f, 0.0f, 0.0f);
   v[10] = SkyboxVertex( 1.0f,  1.0f, -1.0f, 1.0f, 0.0f);
   v[11] = SkyboxVertex( 1.0f,  1.0f,  1.0f, 1.0f, 1.0f);

   v[12] = SkyboxVertex(-1.0f, -1.0f, -1.0f, 0.0f, 1.0f);
   v[13] = SkyboxVertex(-1.0f, -1.0f,  1.0f, 0.0f, 0.0f);
   v[14] = SkyboxVertex( 1.0f, -1.0f,  1.0f, 1.0f, 0.0f);
   v[15] = SkyboxVertex( 1.0f, -1.0f, -1.0f, 1.0f, 1.0f);

   v[16] = SkyboxVertex(-1.0f, -1.0f,  1.0f, 0.0f, 1.0f);
   v[17] = SkyboxVertex(-1.0f,  1.0f,  1.0f, 0.0f, 0.0f);
   v[18] = SkyboxVertex( 1.0f,  1.0f,  1.0f, 1.0f, 0.0f);
   v[19] = SkyboxVertex( 1.0f, -1.0f,  1.0f, 1.0f, 1.0f);

   v[20] = SkyboxVertex( 1.0f, -1.0f, -1.0f, 0.0f, 1.0f);
   v[21] = SkyboxVertex( 1.0f,  1.0f, -1.0f, 0.0f, 0.0f);
   v[22] = SkyboxVertex(-1.0f,  1.0f, -1.0f, 1.0f, 0.0f);
   v[23] = SkyboxVertex(-1.0f, -1.0f, -1.0f, 1.0f, 1.0f);

   SkyboxMesh->UnlockVertexBuffer();

   // Create the index buffer
   WORD* i = 0;
   SkyboxMesh->LockIndexBuffer(0, (void**)&i);

   i[0] = 0; i[1] = 1; i[2] = 2;
   i[3] = 0; i[4] = 2; i[5] = 3;

   i[6] = 4; i[7]  = 5; i[8]  = 6;
   i[9] = 4; i[10] = 6; i[11] = 7;

   i[12] = 8; i[13] =  9; i[14] = 10;
   i[15] = 8; i[16] = 10; i[17] = 11;

   i[18] = 12; i[19] = 13; i[20] = 14;
   i[21] = 12; i[22] = 14; i[23] = 15;

   i[24] = 16; i[25] = 17; i[26] = 18;
   i[27] = 16; i[28] = 18; i[29] = 19;

   i[30] = 20; i[31] = 21; i[32] = 22;
   i[33] = 20; i[34] = 22; i[35] = 23;

   SkyboxMesh->UnlockIndexBuffer();

   //Put each face into a different subset
   DWORD* attributeBuffer = 0;
   SkyboxMesh->LockAttributeBuffer(0, &attributeBuffer);

   for(int a = 0; a < 2; a++)
      attributeBuffer[a] = 0;

   for(int b = 2; b < 4; b++)
      attributeBuffer[b] = 1;

   for(int c = 4; c < 6; c++)
      attributeBuffer[c] = 2;

   for(int d = 6; d < 8; d++)
      attributeBuffer[d] = 3;

   for(int e = 8; e < 10; e++)
      attributeBuffer[e] = 4;

   for(int f = 10; f < 12; f++)
      attributeBuffer[f] = 5;

   SkyboxMesh->UnlockAttributeBuffer();

   std::vector<DWORD> adjacencyBuffer(SkyboxMesh->GetNumFaces() * 3);
   SkyboxMesh->GenerateAdjacency(0.0f, &adjacencyBuffer[0]);

   SkyboxMesh->OptimizeInplace(
   D3DXMESHOPT_ATTRSORT |
   D3DXMESHOPT_COMPACT  |
   D3DXMESHOPT_VERTEXCACHE,
   &adjacencyBuffer[0],
   0, 0, 0);

   //Load the skybox textures
   char* TextureFilenames[6] = { "SkyBox/rt.bmp", "SkyBox/lt.bmp", "SkyBox/up.bmp", "SkyBox/dn.bmp", "SkyBox/ft.bmp", "SkyBox/bk.bmp" };
   for(int i = 0; i < 6; i++)
      D3DXCreateTextureFromFile( D3DDevice, TextureFilenames[i], &SkyboxTextures[i] );
}

///////////////////////////////////////////////////////
// Render the Skybox
///////////////////////////////////////////////////////
void SkyBox::RenderSkybox( IDirect3DDevice9* D3DDevice, D3DXVECTOR3 EyePosition )
{
   D3DXMATRIX SkyboxWorld;
   D3DXMatrixIdentity( &SkyboxWorld );
   SkyboxWorld._41 = EyePosition.x;
   SkyboxWorld._42 = EyePosition.y;
   SkyboxWorld._43 = EyePosition.z;
   D3DDevice->SetTransform(D3DTS_WORLD, &SkyboxWorld);
   D3DDevice->SetRenderState( D3DRS_ZENABLE, false );
   D3DDevice->SetRenderState( D3DRS_ZWRITEENABLE, false );
   D3DDevice->SetSamplerState(0, D3DSAMP_ADDRESSU, D3DTADDRESS_CLAMP);
   D3DDevice->SetSamplerState(0, D3DSAMP_ADDRESSV, D3DTADDRESS_CLAMP);

   for(int i = 0; i < 6; i++)
   {
      D3DDevice->SetTexture( 0, SkyboxTextures[i] );
      SkyboxMesh->DrawSubset(i);
   }

   D3DDevice->SetRenderState( D3DRS_ZENABLE, true);
   D3DDevice->SetRenderState( D3DRS_ZWRITEENABLE, true );
   D3DDevice->SetSamplerState(0, D3DSAMP_ADDRESSU, D3DTADDRESS_WRAP);
   D3DDevice->SetSamplerState(0, D3DSAMP_ADDRESSV, D3DTADDRESS_WRAP);
}

   v[0] = SkyboxVertex( 2.0f, -2.0f,  2.0f, 0.0f, 1.0f);
   v[1] = SkyboxVertex( 2.0f,  2.0f,  2.0f, 0.0f, 0.0f);
   v[2] = SkyboxVertex( 2.0f,  2.0f, -2.0f, 1.0f, 0.0f);
   v[3] = SkyboxVertex( 2.0f, -2.0f, -2.0f, 1.0f, 1.0f);