//=============================================================================
// WalkTerrainDemo.cpp by Frank Luna (C) 2005 All Rights Reserved.
//
// Demonstrates how to walk the camera on the terrain.
//
// Controls: Use mouse to look and 'W', 'S', 'A', and 'D' keys to move.
//=============================================================================

#include "d3dApp.h"
#include "DirectInput.h"
#include <crtdbg.h>
#include "GfxStats.h"
#include <list>
#include "Terrain.h"
#include "Camera.h"

class WalkTerrainDemo : public D3DApp
{
public:
	WalkTerrainDemo(HINSTANCE hInstance, std::string winCaption, D3DDEVTYPE devType, DWORD requestedVP);
	~WalkTerrainDemo();

	bool checkDeviceCaps();
	void onLostDevice();
	void onResetDevice();
	void updateScene(float dt);
	void drawScene();

private:
	GfxStats* mGfxStats;
	Terrain*  mTerrain;
};


int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE prevInstance,
				   PSTR cmdLine, int showCmd)
{
	// Enable run-time memory check for debug builds.
	#if defined(DEBUG) | defined(_DEBUG)
		_CrtSetDbgFlag( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF );
	#endif

	// Construct camera before application, since the application uses the camera.
	Camera camera;
	gCamera = &camera;

	WalkTerrainDemo app(hInstance, "Walk Terrain Demo", D3DDEVTYPE_HAL, D3DCREATE_HARDWARE_VERTEXPROCESSING);
	gd3dApp = &app;

	DirectInput di(DISCL_NONEXCLUSIVE|DISCL_FOREGROUND, DISCL_NONEXCLUSIVE|DISCL_FOREGROUND);
	gDInput = &di;

    return gd3dApp->run();
}

WalkTerrainDemo::WalkTerrainDemo(HINSTANCE hInstance, std::string winCaption, D3DDEVTYPE devType, DWORD requestedVP)
: D3DApp(hInstance, winCaption, devType, requestedVP)
{
	if(!checkDeviceCaps())
	{
		MessageBox(0, "checkDeviceCaps() Failed", 0, 0);
		PostQuitMessage(0);
	}

	InitAllVertexDeclarations();

	mGfxStats = new GfxStats();
	
	// World space units are meters.  So (256*10.0f)x(256*10.0f) is (2.56)^2 square
	// kilometers.
	mTerrain = new Terrain(257, 257, 10.0f, 10.0f, 
		"heightmap17_257.raw",  
		"grass.dds",
		"dirt.dds",
		"stone.dds",
		"blend_hm17.dds",
		3.0f, 0.0f);

	mTerrain->setDirToSunW(D3DXVECTOR3(0.0f, 1.0f, 0.0f));

	mGfxStats->addVertices(mTerrain->getNumVertices());
	mGfxStats->addTriangles(mTerrain->getNumTriangles());

	onResetDevice();
}

WalkTerrainDemo::~WalkTerrainDemo()
{
	delete mGfxStats;
	delete mTerrain;

	DestroyAllVertexDeclarations();
}

bool WalkTerrainDemo::checkDeviceCaps()
{
	D3DCAPS9 caps;
	HR(gd3dDevice->GetDeviceCaps(&caps));

	// Check for vertex shader version 2.0 support.
	if( caps.VertexShaderVersion < D3DVS_VERSION(2, 0) )
		return false;

	// Check for pixel shader version 2.0 support.
	if( caps.PixelShaderVersion < D3DPS_VERSION(2, 0) )
		return false;

	return true;
}

void WalkTerrainDemo::onLostDevice()
{
	mGfxStats->onLostDevice();
	mTerrain->onLostDevice();
}

void WalkTerrainDemo::onResetDevice()
{
	mGfxStats->onResetDevice();
	mTerrain->onResetDevice();


	// The aspect ratio depends on the backbuffer dimensions, which can 
	// possibly change after a reset.  So rebuild the projection matrix.
	float w = (float)md3dPP.BackBufferWidth;
	float h = (float)md3dPP.BackBufferHeight;
	gCamera->setLens(D3DX_PI * 0.25f, w/h, 0.01f, 5000.0f);
}

void WalkTerrainDemo::updateScene(float dt)
{
	mGfxStats->update(dt);

	gDInput->poll();

	gCamera->update(dt, mTerrain, 2.5f);
}

void WalkTerrainDemo::drawScene()
{
	// Clear the backbuffer and depth buffer.
	HR(gd3dDevice->Clear(0, 0, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, 0xffeeeeee, 1.0f, 0));

	HR(gd3dDevice->BeginScene());

	mTerrain->draw();
	
	mGfxStats->display();

	HR(gd3dDevice->EndScene());

	// Present the backbuffer.
	HR(gd3dDevice->Present(0, 0, 0, 0));
}