Contoh program OpenGL berikut ini akan menampilkan tektur merah putih seperti yang rekan-rekan lihat pada gambar di bawah ini.
Tekstur tidak dibuat dengan file bitmap 24 bit, tetapi dengan array 64 X 64 yang diisi dengan nilai RGB 255, 255, 255 untuk menghasilkan warna putih dan nilai 255, 0, 0 untuk menghasilkan warna merah.
Bagi rekan-rekan yag belum memahami tentang RGB silahkan klik link ini untuk menuju ke artikel tentang RGB.
Untuk membuat project silahkan klik link berikut ini, karena sudah pernah ogut bahas sebelumnya.
Nah sampai disini dahulu rekan-rekan, berikut ini ogut juga sertakan source code untuk memudahkan rekan-rekan belajar, serta jangan lupa ada artikel yang terkait dengan artikel ini di bawgian bawah, serta ada link download source code nya juga di bagian bawah. Komplit nya passs.........
#include <windows.h>
#include <gl/gl.h>
#include <stdio.h>
GLuint texture;
#define checkImageWidth 64
#define checkImageHeight 64
GLubyte checkImage[checkImageWidth][checkImageHeight][3];
void makeCheckImage(void)
{
int i, j, c;
for (i = 0; i < checkImageWidth; i++)
{
for (j = 0; j < checkImageHeight; j++)
{
c = ((((i&0x8)==0)^((j&0x8)==0)))* 255;
if (c == 0)
{
//warna putih
checkImage[i][j][0] = (GLubyte) 255;
checkImage[i][j][1] = (GLubyte) 255;
checkImage[i][j][2] = (GLubyte) 255;
}
else
{
//warna merah
checkImage[i][j][0] = (GLubyte) 255;
checkImage[i][j][1] = (GLubyte) 0;
checkImage[i][j][2] = (GLubyte) 0;
}
}
}
}
void myinit(void)
{
makeCheckImage();
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
// Create Texture
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR); //
//scale linearly when image bigger than texture
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); //
glTexImage2D(GL_TEXTURE_2D, 0, 3, checkImageWidth,
checkImageHeight, 0, GL_RGB, GL_UNSIGNED_BYTE,
&checkImage[0][0][0]);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
glEnable(GL_TEXTURE_2D);
glShadeModel(GL_FLAT);
}
void myinit(void);
LRESULT CALLBACK WindowProc(HWND, UINT, WPARAM, LPARAM);
void EnableOpenGL(HWND hwnd, HDC*, HGLRC*);
void DisableOpenGL(HWND, HDC, HGLRC);
int WINAPI WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
WNDCLASSEX wcex;
HWND hwnd;
HDC hDC;
HGLRC hRC;
MSG msg;
BOOL bQuit = FALSE;
float theta = 0.0f;
/* register window class */
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_OWNDC;
wcex.lpfnWndProc = WindowProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance;
wcex.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);
wcex.lpszMenuName = NULL;
wcex.lpszClassName = "GLSample";
wcex.hIconSm = LoadIcon(NULL, IDI_APPLICATION);;
if (!RegisterClassEx(&wcex))
return 0;
/* create main window */
hwnd = CreateWindowEx(0,
"GLSample",
"OpenGL Sample",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
512,
512,
NULL,
NULL,
hInstance,
NULL);
ShowWindow(hwnd, nCmdShow);
/* enable OpenGL for the window */
EnableOpenGL(hwnd, &hDC, &hRC);
myinit();
/* program main loop */
while (!bQuit)
{
/* check for messages */
if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
{
/* handle or dispatch messages */
if (msg.message == WM_QUIT)
{
bQuit = TRUE;
}
else
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
else
{
/* OpenGL animation code goes here */
glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
glClear(GL_COLOR_BUFFER_BIT);
glPushMatrix();
glRotatef(theta / 5.0, 0.0f, 0.0f, 1.0f);
glBindTexture(GL_TEXTURE_2D, texture);
glBegin(GL_POLYGON);
glTexCoord2f(0.0f, 0.0f); glVertex2f(0.0f, 0.0f);
glTexCoord2f(0.0f, 1.0f); glVertex2f(0.0f, 1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex2f(1.0f, 1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex2f(1.0f, 0.0f);
glEnd();
glPopMatrix();
SwapBuffers(hDC);
theta += 1.0f;
Sleep (1);
}
}
/* shutdown OpenGL */
DisableOpenGL(hwnd, hDC, hRC);
/* destroy the window explicitly */
DestroyWindow(hwnd);
return msg.wParam;
}
LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
switch (uMsg)
{
case WM_CLOSE:
PostQuitMessage(0);
break;
case WM_DESTROY:
return 0;
case WM_KEYDOWN:
{
switch (wParam)
{
case VK_ESCAPE:
PostQuitMessage(0);
break;
}
}
break;
default:
return DefWindowProc(hwnd, uMsg, wParam, lParam);
}
return 0;
}
void EnableOpenGL(HWND hwnd, HDC* hDC, HGLRC* hRC)
{
PIXELFORMATDESCRIPTOR pfd;
int iFormat;
/* get the device context (DC) */
*hDC = GetDC(hwnd);
/* set the pixel format for the DC */
ZeroMemory(&pfd, sizeof(pfd));
pfd.nSize = sizeof(pfd);
pfd.nVersion = 1;
pfd.dwFlags = PFD_DRAW_TO_WINDOW |
PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;
pfd.iPixelType = PFD_TYPE_RGBA;
pfd.cColorBits = 24;
pfd.cDepthBits = 16;
pfd.iLayerType = PFD_MAIN_PLANE;
iFormat = ChoosePixelFormat(*hDC, &pfd);
SetPixelFormat(*hDC, iFormat, &pfd);
/* create and enable the render context (RC) */
*hRC = wglCreateContext(*hDC);
wglMakeCurrent(*hDC, *hRC);
}
void DisableOpenGL (HWND hwnd, HDC hDC, HGLRC hRC)
{
wglMakeCurrent(NULL, NULL);
wglDeleteContext(hRC);
ReleaseDC(hwnd, hDC);
}
Salam
Heriady
heriady.yoh@gmail.com
-----------------------------------------------------------------------
-----------------------------------------------------------------------
Tidak ada komentar:
Posting Komentar