#include "DirX9Cls.h"

#define CUSTOMFVF (D3DFVF_XYZRHW | D3DFVF_DIFFUSE)

DirX9Cls::DirX9Cls()
{
}

DirX9Cls::~DirX9Cls()
{
	cleanD3D();
}

void DirX9Cls::initD3D(HWND hWnd, bool fullScreen, UINT screenWidth, UINT screenHeight)
{
	d3d = Direct3DCreate9(D3D_SDK_VERSION); // create the Direct3D interface

	D3DPRESENT_PARAMETERS d3dpp; // create a struct to hold various device information

	::ZeroMemory(&d3dpp, sizeof(d3dpp)); // clear out the struct for use
	d3dpp.Windowed = fullScreen; // program windowed, not fullscreen
	d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD; // discard old frames
	d3dpp.hDeviceWindow = hWnd; // set the window to be used by Direct3D
	d3dpp.BackBufferFormat = D3DFMT_X8R8G8B8; // set the back buffer format to 32-bit
	d3dpp.BackBufferWidth = screenWidth; // set the width of the buffer
	d3dpp.BackBufferHeight = screenHeight; // set the height of the buffer

	// create a device class using this information and information from the d3dpp struct
	d3d->CreateDevice(D3DADAPTER_DEFAULT,
					  D3DDEVTYPE_HAL,
					  hWnd,
					  D3DCREATE_SOFTWARE_VERTEXPROCESSING,
					  &d3dpp,
					  &d3ddev);
	initGraphics(); // call the function to initialize the triangle
}

// this is the function used to render a single frame
void DirX9Cls::renderFrame()
{
	// clear the window to a deep blue
	d3ddev->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0,40,100), 1.0f, 0);
	d3ddev->BeginScene(); // begins the 3d scene
	d3ddev->SetFVF(CUSTOMFVF); // select which vertex format we are using
	d3ddev->SetStreamSource(0, buffer, 0, sizeof(CUSTOMVERTEX)); // select the vertex buffer to display
	d3ddev->DrawPrimitive(D3DPT_TRIANGLELIST, 0, 1); // copy the vertex buffer to the back buffer
	d3ddev->EndScene(); // ends the 3d scene
	d3ddev->Present(NULL, NULL, NULL, NULL); // displays the created frame
}

// this is the function that cleans up Direct3D and COM
void DirX9Cls::cleanD3D()
{
	buffer->Release(); // close and release the vertex buffer
	d3ddev->Release(); // close and release the 3D device
	d3d->Release(); // close and release Direct3D
}

struct DirX9Cls::CUSTOMVERTEX
{
	float x, y, z, rhw; // from the D3DFVF_XYZRHW flag
	DWORD color; // from the D3DFVF_DIFFUSE flag
};

// this is the function that puts the 3D models into the video ram
void DirX9Cls::initGraphics()
{
	// create the vertices using the CUSTOMVERTEX struct
	CUSTOMVERTEX vert[] =
	{
		{320.0f, 50.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0, 0, 255), },
		{520.0f, 400.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0, 255, 0), },
		{120.0f, 400.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(255, 0, 0), },
	};

	// create a vertex buffer interface called buffer
	d3ddev->CreateVertexBuffer(3 * sizeof(CUSTOMVERTEX),
		0,
		CUSTOMFVF,
		D3DPOOL_MANAGED,
		&buffer,
		NULL);
	void* pVoid; // a void pointer

	// lock buffer and load the vertices into it
	buffer->Lock(0, 0, (void**)&pVoid, 0);
	memcpy(pVoid, vert, sizeof(vert));
	buffer->Unlock();
}