Lesson 3: Making game in C++

[Nekochan]

Hey, again....

Click HERE for previous lesson.

Today i will tell about text creating in game.

Information

Hm, lets create R_RenderScene() method between 'BeginScene' and 'EndScene'. It will be better.
There's our final code from second lesson.
I changed code a bit and added R_RenderScene method.

Code:

#include <windows.h>    
#include <windowsx.h>

// required
#include "stdafx.h"

// class
LPCWSTR WIN_MAIN = L"MAIN_WINDOW";

// screen data
int SCREEN_WIDTH;
int SCREEN_HEIGHT;

int SCREEN_POS_X;
int SCREEN_POS_Y;

bool SCREEN_WINDOWED;

LPCWSTR WIN_TITLE;

// d3d data
int D3D_COLOR_R;
int D3D_COLOR_G;
int D3D_COLOR_B;

#include <d3d9.h>
#pragma comment (lib, "d3d9.lib")

LPDIRECT3D9 d3dinit;    // d3d interface init
LPDIRECT3DDEVICE9 d3ddevice;    // d3d device init

// function prototypes
void R_Init(HWND hWnd);    // Initialize d3d device
void R_Frame(void);    // rendering
void CleanD3D(void);    // clear display before showing
void R_Prepare(void);

void R_RenderScene(void);

LRESULT CALLBACK WindowProc(HWND hWnd,
                         UINT message,
                         WPARAM wParam,
                         LPARAM lParam);

int WINAPI WinMain(HINSTANCE hInstance,
                   HINSTANCE hPrevInstance,
                   LPSTR lpCmdLine,
                   int ShowCmd)
{

    R_Prepare();

    // Window creation
    MSG msg;
    WNDCLASSEX wc = {sizeof(WNDCLASSEX), CS_VREDRAW|CS_HREDRAW|CS_OWNDC,
                    WindowProc, 0, 0, hInstance, NULL, NULL, (HBRUSH)(COLOR_WINDOW+3),
                    NULL, WIN_MAIN, NULL};

    RegisterClassEx(&wc);

    // create new window
    HWND hMainWnd = CreateWindow(WIN_MAIN,
                                WIN_TITLE,
                                WS_OVERLAPPEDWINDOW, SCREEN_POS_X, SCREEN_POS_Y, SCREEN_WIDTH, SCREEN_HEIGHT,

                                NULL, NULL, hInstance, NULL);
    // show it
    ShowWindow(hMainWnd, ShowCmd);

    // INIT DIRECT3D
    R_Init(hMainWnd); // Initialize d3d stuff
    
    UpdateWindow(hMainWnd);

    // real time loop
    while(TRUE)
    {
        while(PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
        {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
        // game loop can be there

        if(msg.message == WM_QUIT)
            break;

        // game loop can be there // recommended there
        R_Frame();
    }

    CleanD3D();

   return(0);
}

LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch(message)
    {
        case WM_DESTROY:
            PostQuitMessage(0);
            return(0);
    }

    return DefWindowProc (hWnd, message, wParam, lParam);
}

// ===== Prepare stuff ===== //
void R_Prepare(void)
{
    // mode
    SCREEN_WINDOWED = TRUE;

    // size of window
    SCREEN_WIDTH = 1024;
    SCREEN_HEIGHT = 768;
    // position of window
    SCREEN_POS_X = 0;
    SCREEN_POS_Y = 0;

    // title of the window
    WIN_TITLE = L"Windowed program ^_^"; // L prefix is required ( C++ basics )

    // d3d clear color data
    // blueness
    D3D_COLOR_R = 0;
    D3D_COLOR_G = 40;
    D3D_COLOR_B = 120;
}

// ===== Direct3D stuff ===== //

// init Direct3D
void R_Init(HWND hWnd)
{
    d3dinit = Direct3DCreate9(D3D_SDK_VERSION);    // interface creationism

    // presentation parameters
    D3DPRESENT_PARAMETERS d3dparams;

    ZeroMemory(&d3dparams, sizeof(d3dparams));    // clear d3d parameters

    d3dparams.Windowed = SCREEN_WINDOWED;    // window mode toggle
    d3dparams.SwapEffect = D3DSWAPEFFECT_DISCARD;   // available: D3DSWAPEFFECT_FLIP, D3DSWAPEFFECT_COPY
    d3dparams.hDeviceWindow = hWnd;    // get owner and set d3d to the window

    d3dinit->CreateDevice(D3DADAPTER_DEFAULT,
                      D3DDEVTYPE_HAL,
                      hWnd, // window owner
                      D3DCREATE_SOFTWARE_VERTEXPROCESSING,
                      &d3dparams, // presentation parameters
                      &d3ddevice); // initialized device
}

// Render
// this is the function used to render a single frame
void R_Frame(void)
{
    // clear current window
    d3ddevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(D3D_COLOR_R, D3D_COLOR_G, D3D_COLOR_B), 1.0f, 0);

    d3ddevice->BeginScene();    // starts rendering current scene

    // your rendering stuff will be there
    R_RenderScene();

    d3ddevice->EndScene();    // stops rendering current scene

    d3ddevice->Present(NULL, NULL, NULL, NULL);    // shows current scene
}

// Clean d3d
void CleanD3D(void)
{
    d3ddevice->Release();    // destroys d3d device
    d3dinit->Release();    // destroys d3d stuffs
}

// Render your stuff
void R_RenderScene(void)
{

}

So, lets make font rendering
Firstly, you need to add new header and library files.

Code:

#include <d3dx9.h> // added
#pragma comment (lib, "d3dx9.lib") // added

Required for fonts and another stuff.
Let's add two methods, Font_Init and R_DrawString.

Code:

void Font_Init(LPCWSTR fontname); // font name can be Arial, etc
void R_DrawString(LPCWSTR string, int x, int y, D3DCOLOR fontcolor);

To create font prototype we will use

Code:

LPD3DXFONT g_font;

So, lets create functions and text rendering!

Text rendering, preparing

Lets create Font_Init method. It's just one line.

Code:

D3DXCreateFont( d3ddevice, FONT_HEIGHT, FONT_WIDTH, FW_BOLD, 0, FALSE, DEFAULT_CHARSET, OUT_DEFAULT_PRECIS, DEFAULT_QUALITY, DEFAULT_PITCH | FF_DONTCARE, fontname, &g_font );

d3ddevice - Our current D3D Device
FONT_HEIGHT and FONT_WIDTH are integers, i included them in my code.

Code:

int FONT_HEIGHT;
int FONT_WIDTH;

fontname - Name of font which will be used to draw text. I will use Arial.
g_font - out for g_font global variable.
Another parameters are not so important.
That what you must get

Code:

int FONT_HEIGHT;
int FONT_WIDTH;

// create fonts
void Font_Init(LPCWSTR fontname)
{
    FONT_HEIGHT = 15;
    // crete new d3d font
    D3DXCreateFont( d3ddevice, FONT_HEIGHT, FONT_WIDTH, FW_BOLD, 0, FALSE, DEFAULT_CHARSET, OUT_DEFAULT_PRECIS, DEFAULT_QUALITY, DEFAULT_PITCH | FF_DONTCARE, fontname, &g_font );
}

Font_Init initializes in R_Init, AFTER ALL ( since it is using d3ddevice, which is initializing )

This line creates d3d font, but it won't show. Now we need to create font itself and set font data. ( Position, color etc )
We will use R_DrawString method Rectangle class.
Let me explain you, how to make it.

Lets create rectangle first

Code:

    RECT rectangle;

Now set some parameters

Code:

    rectangle.left = x; // X position
    rectangle.right = SCREEN_HEIGHT; // set right position for text
    rectangle.top = y; // Y position
    rectangle.bottom = rectangle.top + 30; // just more space

x and y are parameters in R_DrawString

The following line of code is drawing text with data.

Code:

    // render our text
    g_font->DrawText(NULL, string, -1, &rectangle, 0, fontcolor );

string is our text in parameters.

There's final function

Code:

void R_DrawString(LPCWSTR string, int x, int y, D3DCOLOR fontcolor)
{
    RECT rectangle;
    rectangle.left = x; // x pos
    rectangle.right = SCREEN_HEIGHT; // right coords
    rectangle.top = y; // y pos
    rectangle.bottom = rectangle.top + 30; // just more space

    // render our text
    g_font->DrawText(NULL, string, -1, &rectangle, 0, fontcolor );
}

So, uh, we made font stuff. Lets show it!
As you remember, i've created R_RenderScene. Put R_DrawString in this method.
Example of using:

Code:

// Render your stuff
void R_RenderScene(void)
{
    // draw string
    // 255 255 255 - white
        //                  // string               x    y    color
    R_DrawString(L"Hello ItsMods!", 10, 10, D3DCOLOR_ARGB(255,255,255,255));
}

Press Compile, Run it, and you will see that:


Final code:

Code:

#include <windows.h>    
#include <windowsx.h>

// required
#include "stdafx.h"

// class
LPCWSTR WIN_MAIN = L"MAIN_WINDOW";

// screen data
int SCREEN_WIDTH;
int SCREEN_HEIGHT;

int SCREEN_POS_X;
int SCREEN_POS_Y;

bool SCREEN_WINDOWED;

LPCWSTR WIN_TITLE;

// d3d data
int D3D_COLOR_R;
int D3D_COLOR_G;
int D3D_COLOR_B;

#include <d3d9.h>
#include <d3dx9.h> // added

#pragma comment (lib, "d3dx9.lib") // added
#pragma comment (lib, "d3d9.lib")

LPDIRECT3D9 d3dinit;    // d3d interface init
LPDIRECT3DDEVICE9 d3ddevice;    // d3d device init

// function prototypes
void R_Init(HWND hWnd);    // Initialize d3d device
void R_Frame(void);    // rendering
void CleanD3D(void);    // clear display before showing
void R_Prepare(void);

void R_RenderScene(void);

// font stuff
void Font_Init(LPCWSTR fontname);
void R_DrawString(LPCWSTR string, int x, int y, D3DCOLOR fontcolor);


LRESULT CALLBACK WindowProc(HWND hWnd,
                         UINT message,
                         WPARAM wParam,
                         LPARAM lParam);

int WINAPI WinMain(HINSTANCE hInstance,
                   HINSTANCE hPrevInstance,
                   LPSTR lpCmdLine,
                   int ShowCmd)
{

    R_Prepare();

    // Window creation
    MSG msg;
    WNDCLASSEX wc = {sizeof(WNDCLASSEX), CS_VREDRAW|CS_HREDRAW|CS_OWNDC,
                    WindowProc, 0, 0, hInstance, NULL, NULL, (HBRUSH)(COLOR_WINDOW+3),
                    NULL, WIN_MAIN, NULL};

    RegisterClassEx(&wc);

    // create new window
    HWND hMainWnd = CreateWindow(WIN_MAIN,
                                WIN_TITLE,
                                WS_OVERLAPPEDWINDOW, SCREEN_POS_X, SCREEN_POS_Y, SCREEN_WIDTH, SCREEN_HEIGHT,

                                NULL, NULL, hInstance, NULL);
    // show it
    ShowWindow(hMainWnd, ShowCmd);

    // INIT DIRECT3D
    R_Init(hMainWnd); // Initialize d3d stuff
    
    UpdateWindow(hMainWnd);

    // real time loop
    while(TRUE)
    {
        while(PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
        {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }
        // game loop can be there

        if(msg.message == WM_QUIT)
            break;

        // game loop can be there // recommended there
        R_Frame();
    }

    CleanD3D();

   return(0);
}

LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch(message)
    {
        case WM_DESTROY:
            PostQuitMessage(0);
            return(0);
    }

    return DefWindowProc (hWnd, message, wParam, lParam);
}

// ===== Prepare stuff ===== //
void R_Prepare(void)
{
    // mode
    SCREEN_WINDOWED = TRUE;

    // size of window
    SCREEN_WIDTH = 1024;
    SCREEN_HEIGHT = 768;
    // position of window
    SCREEN_POS_X = 0;
    SCREEN_POS_Y = 0;

    // title of the window
    WIN_TITLE = L"Windowed program ^_^"; // L prefix is required ( C++ basics )

    // d3d clear color data
    // blueness
    D3D_COLOR_R = 0;
    D3D_COLOR_G = 40;
    D3D_COLOR_B = 120;
}

// ===== Direct3D stuff ===== //

// init Direct3D
void R_Init(HWND hWnd)
{
    d3dinit = Direct3DCreate9(D3D_SDK_VERSION);    // interface creationism

    // presentation parameters
    D3DPRESENT_PARAMETERS d3dparams;

    ZeroMemory(&d3dparams, sizeof(d3dparams));    // clear d3d parameters

    d3dparams.Windowed = SCREEN_WINDOWED;    // window mode toggle
    d3dparams.SwapEffect = D3DSWAPEFFECT_DISCARD;   // available: D3DSWAPEFFECT_FLIP, D3DSWAPEFFECT_COPY
    d3dparams.hDeviceWindow = hWnd;    // get owner and set d3d to the window

    d3dinit->CreateDevice(D3DADAPTER_DEFAULT,
                      D3DDEVTYPE_HAL,
                      hWnd, // window owner
                      D3DCREATE_SOFTWARE_VERTEXPROCESSING,
                      &d3dparams, // presentation parameters
                      &d3ddevice); // initialized device

    // initialize fonts
    Font_Init(L"Arial");
}

// Render
// this is the function used to render a single frame
void R_Frame(void)
{
    // clear current window
    d3ddevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(D3D_COLOR_R, D3D_COLOR_G, D3D_COLOR_B), 1.0f, 0);

    d3ddevice->BeginScene();    // starts rendering current scene

    // your rendering stuff will be there
    R_RenderScene();

    d3ddevice->EndScene();    // stops rendering current scene

    d3ddevice->Present(NULL, NULL, NULL, NULL);    // shows current scene
}

// Clean d3d
void CleanD3D(void)
{
    d3ddevice->Release();    // destroys d3d device
    d3dinit->Release();    // destroys d3d stuffs
}
// =================================================================== //

// font
LPD3DXFONT g_font;
int FONT_HEIGHT;
int FONT_WIDTH;

// create fonts
void Font_Init(LPCWSTR fontname)
{
    FONT_HEIGHT = 30;
    // crete new d3d font
    D3DXCreateFont( d3ddevice, FONT_HEIGHT, FONT_WIDTH, FW_BOLD, 0, FALSE, DEFAULT_CHARSET, OUT_DEFAULT_PRECIS, DEFAULT_QUALITY, DEFAULT_PITCH | FF_DONTCARE, fontname, &g_font );
}

// render fonts
void R_DrawString(LPCWSTR string, int x, int y, D3DCOLOR fontcolor)
{
    RECT rectangle;
    rectangle.left = x; // x pos
    rectangle.right = SCREEN_HEIGHT; // right coords
    rectangle.top = y; // y pos
    rectangle.bottom = rectangle.top + 30; // just more space

    // render our text
    g_font->DrawText(NULL, string, -1, &rectangle, 0, fontcolor );
}

// =================================================================== //
// Render your stuff
void R_RenderScene(void)
{
    // draw string
    // 255 255 255 - white
    R_DrawString(L"Hello ItsMods!", 10, 10, D3DCOLOR_ARGB(255,255,255,255));
}

Well, it's just 2D stuff, in next tutorial i will tell about 3D stuff and more.

[EnVi Sweden Rocks]

when will lesson 4 come?

[Nekochan]

Maybe i will do opengl lessons