Книга: DirectX 8 Programming Tutorial

Colours

To represent colours in Direct X, we use the D3DCOLOR_XRGB macro. There are three parameters: Red, Green and Blue. These parameters are integer values between 0 and 255. By specifying different red, green and blue values (mixing colours) you can make any colour you need.

For example:

D3DCOLOR_XRGB(0, 0, 0) is black (no colour)

D3DCOLOR_XRGB(255, 255, 255) is white (full colour)

D3DCOLOR_XRGB(0, 255, 0) is bright green (no red, full green, no blue)

D3DCOLOR_XRGB(100, 20, 100) is dark purple (100 red, 20 green, 100 blue)

Here is the code for this tutorial. It's just the same as the code from the first tutorial, except for a few modifications:

#include <d3d8.h>
LPDIRECT3D8 g_pD3D = NULL;
LPDIRECT3DDEVICE8 g_pD3DDevice = NULL;
LPDIRECT3DVERTEXBUFFER8 g_pVertexBuffer = NULL; // Buffer to hold vertices
struct CUSTOMVERTEX {
 FLOAT x, y, z, rhw; // The transformed position for the vertex.
 DWORD colour; // The vertex colour.
};
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZRHW|D3DFVF_DIFFUSE)
#define SafeRelease(pObject) if(pObject != NULL) {pObject->Release(); pObject=NULL;}
HRESULT InitialiseD3D(HWND hWnd) {
 //First of all, create the main D3D object. If it is created successfully we
 //should get a pointer to an IDirect3D8 interface.
 g_pD3D = Direct3DCreate8(D3D_SDK_VERSION);
 if (g_pD3D == NULL) {
  return E_FAIL;
 }
 //Get the current display mode
 D3DDISPLAYMODE d3ddm;
 if (FAILED(g_pD3D->GetAdapterDisplayMode(D3DADAPTER_DEFAULT, &d3ddm))) {
  return E_FAIL;
 }
 //Create a structure to hold the settings for our device
 D3DPRESENT_PARAMETERS d3dpp;
 ZeroMemory(&d3dpp, sizeof(d3dpp));
 //Fill the structure.
 //We want our program to be windowed, and set the back buffer to a format
 //that matches our current display mode
 d3dpp.Windowed = TRUE;
 d3dpp.SwapEffect = D3DSWAPEFFECT_COPY_VSYNC;
 d3dpp.BackBufferFormat = d3ddm.Format;
 //Create a Direct3D device.
 if (FAILED(g_pD3D->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd, D3DCREATE_SOFTWARE_VERTEXPROCESSING, &d3dpp, &g_pD3DDevice))) {
  return E_FAIL;
 }
 return S_OK;
}
HRESULT InitialiseVertexBuffer() {
 VOID* pVertices;
 //Store each point of the triangle together with it's colour
 CUSTOMVERTEX cvVertices[] = {
  {250.0f, 100.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(255, 0, 0),}, //Vertex 1 – Red (250, 100)
  {400.0f, 350.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0, 255, 0),}, //Vertex 2 – Green (400, 350)
  {100.0f, 350.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0, 0, 255),}, //Vertex 3 – Blue (100, 350)
 };
 //Create the vertex buffer from our device
 if (FAILED(g_pD3DDevice->CreateVertexBuffer(3 * sizeof(CUSTOMVERTEX), 0, D3DFVF_CUSTOMVERTEX, D3DPOOL_DEFAULT, &g_pVertexBuffer))) {
  return E_FAIL;
 }
 //Get a pointer to the vertex buffer vertices and lock the vertex buffer
 if (FAILED(g_pVertexBuffer->Lock(0, sizeof(cvVertices), (BYTE**)&pVertices, 0))) {
  return E_FAIL;
 }
 //Copy our stored vertices values into the vertex buffer
 memcpy(pVertices, cvVertices, sizeof(cvVertices));
 //Unlock the vertex buffer
 g_pVertexBuffer->Unlock();
 return S_OK;
}
void Render() {
 if (g_pD3DDevice == NULL) {
  return;
 }
 //Clear the backbuffer to black
 g_pD3DDevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
 //Begin the scene
 g_pD3DDevice->BeginScene();
 //Rendering our triangle
 g_pD3DDevice->SetStreamSource(0, g_pVertexBuffer, sizeof(CUSTOMVERTEX));
 g_pD3DDevice->SetVertexShader(D3DFVF_CUSTOMVERTEX);
 g_pD3DDevice->DrawPrimitive(D3DPT_TRIANGLELIST, 0, 1);
 //End the scene
 g_pD3DDevice->EndScene();
 //Filp the back and front buffers so that whatever has been rendered on the back buffer
 //will now be visible on screen (front buffer).
 g_pD3DDevice->Present(NULL, NULL, NULL, NULL);
}
void CleanUp() {
 SafeRelease(g_pVertexBuffer);
 SafeRelease(g_pD3DDevice);
 SafeRelease(g_pD3D);
}
void GameLoop() {
 //Enter the game loop
 MSG msg;
 BOOL fMessage;
 PeekMessage(&msg, NULL, 0U, 0U, PM_NOREMOVE);
 while (msg.message != WM_QUIT) {
  fMessage = PeekMessage(&msg, NULL, 0U, 0U, PM_REMOVE);
  if (fMessage) {
   //Process message
   TranslateMessage(&msg);
   DispatchMessage(&msg);
  } else {
   //No message to process, so render the current scene
   Render();
  }
 }
}
//The windows message handler
LRESULT WINAPI WinProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam) {
 switch(msg) {
 case WM_DESTROY:
  PostQuitMessage(0);
  return 0;
  break;
 case WM_KEYUP:
  switch (wParam) {
  case VK_ESCAPE:
   //User has pressed the escape key, so quit
   DestroyWindow(hWnd);
   return 0;
   break;
  }
  break;
 }
 return DefWindowProc(hWnd, msg, wParam, lParam);
}
//Application entry point
INT WINAPI WinMain(HINSTANCE hInst, HINSTANCE, LPSTR, INT) {
 //Register the window class
 WNDCLASSEX wc = {
  sizeof(WNDCLASSEX), CS_CLASSDC, WinProc, 0L, 0L, GetModuleHandle(NULL), NULL, NULL, NULL, NULL, "DX Project 2", NULL
 };
 RegisterClassEx(&wc);
 //Create the application's window
 HWND hWnd = CreateWindow("DX Project 2", "www.andypike.com: Tutorial 2", WS_OVERLAPPEDWINDOW, 50, 50, 500, 500, GetDesktopWindow(), NULL, wc.hInstance, NULL);
 //Initialize Direct3D
 if (SUCCEEDED(InitialiseD3D(hWnd))) {
  //Show our window
  ShowWindow(hWnd, SW_SHOWDEFAULT);
  UpdateWindow(hWnd);
  //Initialize Vertex Buffer
  if (SUCCEEDED(InitialiseVertexBuffer())) {
   //Start game running: Enter the game loop
   GameLoop();
  }
 }
 CleanUp();
 UnregisterClass("DX Project 2", wc.hInstance);
 return 0;
}

You should finish up with a window with a black background and a multi-coloured triangle in the middle (shown below).

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