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What I want?
To switch as fast as possible between 2 background color ( lets say white and red ) to be more specific, I want the screen always be white and for 1 frame ( this has so short ) be red every lets say 500ms
What I know?
Well not much , I'm looking all day so simple example but all I can find is so complex comparing to what I want, so any simple tutorial accepted with a smile :)
Why I'm using DirectX?
I tried to do it on OpenGL without success and here someone told me I should use this, but I don't know how and couldn't find where to learn... The version of the DX isn't important to me, I just need it to be as fast as possible..
So, I hope you will help me, thanks anyway :)

UPDATE : STILL GOT NO ANSWER

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Hido
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1 Answers1

2

I make an offer that i hope can help you. try these steps :

include the basic windows header files and the Direct3D header file :

#include <windows.h>
#include <windowsx.h>
#include <d3d9.h>

include the Direct3D Library file :

#pragma comment (lib, "d3d9.lib")

then add below codes too :

// global declarations
LPDIRECT3D9 d3d;    // the pointer to our Direct3D interface
LPDIRECT3DDEVICE9 d3ddev;    // the pointer to the device class

// function prototypes
void initD3D(HWND hWnd);    // sets up and initializes Direct3D
void render_frame(void);    // renders a single frame
void cleanD3D(void);    // closes Direct3D and releases memory

// the WindowProc function prototype
LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);


// the entry point for any Windows program
int WINAPI WinMain(HINSTANCE hInstance,
                   HINSTANCE hPrevInstance,
                   LPSTR lpCmdLine,
                   int nCmdShow)
{
    HWND hWnd;
    WNDCLASSEX wc;

    ZeroMemory(&wc, sizeof(WNDCLASSEX));

    wc.cbSize = sizeof(WNDCLASSEX);
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = (WNDPROC)WindowProc;
    wc.hInstance = hInstance;
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)COLOR_WINDOW;
    wc.lpszClassName = L"WindowClass";

    RegisterClassEx(&wc);

    hWnd = CreateWindowEx(NULL,
                          L"WindowClass",
                          L"Our First Direct3D Program",
                          WS_OVERLAPPEDWINDOW,
                          300, 300,
                          640, 480,
                          NULL,
                          NULL,
                          hInstance,
                          NULL);

    ShowWindow(hWnd, nCmdShow);

    // set up and initialize Direct3D
    initD3D(hWnd);

    // enter the main loop:

    MSG msg;

    while(TRUE)
    {
        DWORD starting_point = GetTickCount();

        if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
        {
            if (msg.message == WM_QUIT)
                break;

            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }

        render_frame();

        while ((GetTickCount() - starting_point) < 25);
    }

    // clean up DirectX and COM
    cleanD3D();

    return msg.wParam;
}

// this is the main message handler for the program
LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch(message)
    {
        case WM_DESTROY:
            {
                PostQuitMessage(0);
                return 0;
            } break;
    }

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

// this function initializes and prepares Direct3D for use
void initD3D(HWND hWnd)
{
    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 = TRUE;    // program windowed, not fullscreen
    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;    // discard old frames
    d3dpp.hDeviceWindow = hWnd;    // set the window to be used by Direct3D


    // create a device class using this information and the info from the d3dpp stuct
    d3d->CreateDevice(D3DADAPTER_DEFAULT,
                      D3DDEVTYPE_HAL,
                      hWnd,
                      D3DCREATE_SOFTWARE_VERTEXPROCESSING,
                      &d3dpp,
                      &d3ddev);

    return;
}

// this is the function used to render a single frame
void render_frame(void)
{
    d3ddev->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 40, 100), 1.0f, 0);

    d3ddev->BeginScene();    // begins the 3D scene

    // do 3D rendering here

    d3ddev->EndScene();    // ends the 3D scene

    d3ddev->Present(NULL, NULL, NULL, NULL);   // displays the created frame on the screen

    return;
}

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

    return;
}
  • Thank you for answering! but, I just see a blue screen, how can I verify that 1 frame was red ? Usually what I do is use `Sleep(500)` before I back to the original number but here I don't understand where do I need to put it. – Hido Apr 25 '17 at 14:29
  • @Peewe take a look at this [link](https://www.gamedev.net/topic/519829-changing-background-color-during-runtime/) – BattleTested_закалённый в бою Apr 25 '17 at 14:49
  • All I needed to do is to call to the `render_frame` another time. Thank you! – Hido Apr 25 '17 at 15:00
  • Up-voted , but there is a problem , I captured my screen with 60FPS recorder and than play it with slow motion and the red screen stays for ~120ms which is like almost 10 frames instead of 1... Do you have better way ? In your program you're using double buffering and Vsync? – Hido Apr 25 '17 at 15:19
  • @Peewe i dont know, in this program i used of [this page](https://www.gamedev.net/topic/519829-changing-background-color-during-runtime/) to guide you. but i researched many pages about Vsync as below : [link1](https://gamedev.stackexchange.com/questions/11969/fullscreen-vsync-stuttering), [link2](http://stackoverflow.com/questions/16856115/turned-off-vsync-but-still-getting-60fps-in-my-directx-9-application), [link3](http://stackoverflow.com/questions/3915416/how-to-enable-vsync-in-d3d-windowed-app). apologies if i cant help more... – BattleTested_закалённый в бою Apr 25 '17 at 16:07
  • That's not what I'm looking for.. thanks anyway :) I'll wait for more answers. – Hido Apr 25 '17 at 16:15