本课NeHe给大家实现了一个简单的粒子系统。
需要的图片在这里。
代码如下：
#include<windows.h>//vs2008,windows.h has glaut.h
#include<tchar.h>
#include <gl\gl.h>
#include <gl\glu.h>
#pragma comment(lib,"opengl32.lib")
#pragma comment(lib,"glu32.lib")
#define MAX_PARTICLES 1000 // Number Of Particles To Create ( NEW )
HGLRC hRC=NULL; // Permanent Rendering Context
HDC hDC=NULL; // Private GDI Device Context
HWND hWnd=NULL; // Holds Our Window Handle
HINSTANCE hInstance; // Holds The Instance Of The Application
bool keys[256]; // Array Used For The Keyboard Routine
bool active=TRUE; // Window Active Flag Set To TRUE By Default
bool fullscreen=FALSE; // no Fullscreen Flag Set To Fullscreen Mode By Default
bool rainbow=true; // Rainbow Mode? ( ADD )
bool sp; // Spacebar Pressed? ( ADD )
bool rp; // Return Key Pressed? ( ADD )
float slowdown=0.02f; // Slow Down Particles
float xspeed; // Base X Speed (To Allow Keyboard Direction Of Tail)
float yspeed; // Base Y Speed (To Allow Keyboard Direction Of Tail)
float zoom=-40.0f; // Used To Zoom Out
GLuint loop; // Misc Loop Variable
GLuint col; // Current Color Selection
GLuint delay; // Rainbow Effect Delay
GLuint texture[1]; // Storage For Our Particle Texture
typedef struct // Create A Structure For Particle
{
bool active; // Active (Yes/No)
float life; // Particle Life
float fade; // Fade Speed
float r; // Red Value
float g; // Green Value
float b; // Blue Value
float x; // X Position
float y; // Y Position
float z; // Z Position
float xi; // X Direction
float yi; // Y Direction
float zi; // Z Direction
float xg; // X Gravity
float yg; // Y Gravity
float zg; // Z Gravity
}particles; // Particles Structure
particles particle[MAX_PARTICLES]; // Particle Array (Room For Particle Info)
static GLfloat colors[12][3]= // Rainbow Of Colors
{
{1.0f,0.5f,0.5f},{1.0f,0.75f,0.5f},{1.0f,1.0f,0.5f},{0.75f,1.0f,0.5f},
{0.5f,1.0f,0.5f},{0.5f,1.0f,0.75f},{0.5f,1.0f,1.0f},{0.5f,0.75f,1.0f},
{0.5f,0.5f,1.0f},{0.75f,0.5f,1.0f},{1.0f,0.5f,1.0f},{1.0f,0.5f,0.75f}
};
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM); // Declaration For WndProc
bool NeHeLoadBitmap(LPTSTR szFileName, GLuint *texid) // Creates Texture From A Bitmap File
{
HBITMAP hBMP; // Handle Of The Bitmap
BITMAP BMP; // Bitmap Structure
glGenTextures(1, texid); // Create The Texture
hBMP=(HBITMAP)LoadImage(GetModuleHandle(NULL), szFileName, IMAGE_BITMAP, 0, 0, LR_CREATEDIBSECTION | LR_LOADFROMFILE );
if (!hBMP) // Does The Bitmap Exist?
return FALSE; // If Not Return False
GetObject(hBMP, sizeof(BMP), &BMP); // Get The Object
// hBMP: Handle To Graphics Object
// sizeof(BMP): Size Of Buffer For Object Information
// &BMP: Buffer For Object Information
glPixelStorei(GL_UNPACK_ALIGNMENT, 4); // Pixel Storage Mode (Word Alignment / 4 Bytes)
// Typical Texture Generation Using Data From The Bitmap
glBindTexture(GL_TEXTURE_2D, *texid); // Bind To The Texture ID
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); // Linear Min Filter
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // Linear Mag Filter
glTexImage2D(GL_TEXTURE_2D, 0, 3, BMP.bmWidth, BMP.bmHeight, 0, GL_BGR_EXT, GL_UNSIGNED_BYTE, BMP.bmBits);
DeleteObject(hBMP); // Delete The Object
return TRUE; // Loading Was Successful
}
GLvoid ReSizeGLScene(GLsizei width, GLsizei height) // Resize And Initialize The GL Window
{
if (height==0) // Prevent A Divide By Zero By
{
height=1; // Making Height Equal One
}
glViewport(0, 0, width, height); // Reset The Current Viewport
glMatrixMode(GL_PROJECTION); // Select The Projection Matrix
glLoadIdentity(); // Reset The Projection Matrix
// Calculate The Aspect Ratio Of The Window
gluPerspective(45.0f,(GLfloat)width/(GLfloat)height,0.1f,200.0f);
glMatrixMode(GL_MODELVIEW); // Select The Modelview Matrix
glLoadIdentity(); // Reset The Modelview Matrix
}//end of ReSizeGLScene
int InitGL(GLvoid) // All Setup For OpenGL Goes Here
{
if (!NeHeLoadBitmap(_T("Data\\Particle.bmp"), &texture[0])) // Load The Bitmap
{
return FALSE; // If Texture Didn't Load Return FALSE ( NEW )
}
glShadeModel(GL_SMOOTH); // Enables Smooth Shading
glClearColor(0.0f,0.0f,0.0f,0.0f); // Black Background
glClearDepth(1.0f); // Depth Buffer Setup
glDisable(GL_DEPTH_TEST); // Disables Depth Testing
glEnable(GL_BLEND); // Enable Blending
glBlendFunc(GL_SRC_ALPHA,GL_ONE); // Type Of Blending To Perform
glHint(GL_PERSPECTIVE_CORRECTION_HINT,GL_NICEST); // Really Nice Perspective Calculations
glHint(GL_POINT_SMOOTH_HINT,GL_NICEST); // Really Nice Point Smoothing
glEnable(GL_TEXTURE_2D); // Enable Texture Mapping
glBindTexture(GL_TEXTURE_2D,texture[0]); // Select Our Texture
for (loop=0;loop<MAX_PARTICLES;loop++) // Initialize All The Textures
{
particle[loop].active=true; // Make All The Particles Active
particle[loop].life=1.0f; // Give All The Particles Full Life
particle[loop].fade=float(rand()%100)/1000.0f+0.003f; // Random Fade Speed
particle[loop].r=colors[loop*(12/MAX_PARTICLES)][0]; // Select Red Rainbow Color
particle[loop].g=colors[loop*(12/MAX_PARTICLES)][1]; // Select Red Rainbow Color
particle[loop].b=colors[loop*(12/MAX_PARTICLES)][2]; // Select Red Rainbow Color
particle[loop].xi=float((rand()%50)-26.0f)*10.0f; // Random Speed On X Axis
particle[loop].yi=float((rand()%50)-25.0f)*10.0f; // Random Speed On Y Axis
particle[loop].zi=float((rand()%50)-25.0f)*10.0f; // Random Speed On Z Axis
particle[loop].xg=0.0f; // Set Horizontal Pull To Zero
particle[loop].yg=-0.8f; // Set Vertical Pull Downward
particle[loop].zg=0.0f; // Set Pull On Z Axis To Zero
}
return TRUE; // Initialization Went OK
}//end of InitGL
int DrawGLScene(GLvoid) // Here's Where We Do All The Drawing
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer
glLoadIdentity(); // Reset The Current Modelview Matrix
//
//TODO:the code of openGL
//
for (loop=0;loop<MAX_PARTICLES;loop++) // Loop Through All The Particles
{
if (particle[loop].active) // If The Particle Is Active
{
float x=particle[loop].x; // Grab Our Particle X Position
float y=particle[loop].y; // Grab Our Particle Y Position
float z=particle[loop].z+zoom; // Particle Z Pos + Zoom
// Draw The Particle Using Our RGB Values, Fade The Particle Based On It's Life
glColor4f(particle[loop].r,particle[loop].g,particle[loop].b,particle[loop].life);
glBegin(GL_TRIANGLE_STRIP); // Build Quad From A Triangle Strip
glTexCoord2d(1,1); glVertex3f(x+0.5f,y+0.5f,z); // Top Right
glTexCoord2d(0,1); glVertex3f(x-0.5f,y+0.5f,z); // Top Left
glTexCoord2d(1,0); glVertex3f(x+0.5f,y-0.5f,z); // Bottom Right
glTexCoord2d(0,0); glVertex3f(x-0.5f,y-0.5f,z); // Bottom Left
glEnd(); // Done Building Triangle Strip
particle[loop].x+=particle[loop].xi/(slowdown*1000); // Move On The X Axis By X Speed
particle[loop].y+=particle[loop].yi/(slowdown*1000); // Move On The Y Axis By Y Speed
particle[loop].z+=particle[loop].zi/(slowdown*1000); // Move On The Z Axis By Z Speed
particle[loop].xi+=particle[loop].xg; // Take Pull On X Axis Into Account
particle[loop].yi+=particle[loop].yg; // Take Pull On Y Axis Into Account
particle[loop].zi+=particle[loop].zg; // Take Pull On Z Axis Into Account
particle[loop].life-=particle[loop].fade; // Reduce Particles Life By 'Fade'
if (particle[loop].life<0.0f) // If Particle Is Burned Out
{
particle[loop].life=1.0f; // Give It New Life
particle[loop].fade=float(rand()%100)/1000.0f+0.003f; // Random Fade Value
particle[loop].x=0.0f; // Center On X Axis
particle[loop].y=0.0f; // Center On Y Axis
particle[loop].z=0.0f; // Center On Z Axis
particle[loop].xi=xspeed+float((rand()%60)-32.0f); // X Axis Speed And Direction
particle[loop].yi=yspeed+float((rand()%60)-30.0f); // Y Axis Speed And Direction
particle[loop].zi=float((rand()%60)-30.0f); // Z Axis Speed And Direction
particle[loop].r=colors[col][0]; // Select Red From Color Table
particle[loop].g=colors[col][1]; // Select Green From Color Table
particle[loop].b=colors[col][2]; // Select Blue From Color Table
}
// If Number Pad 8 And Y Gravity Is Less Than 1.5 Increase Pull Upwards
if (keys[VK_NUMPAD8] && (particle[loop].yg<1.5f)) particle[loop].yg+=0.01f;
// If Number Pad 2 And Y Gravity Is Greater Than -1.5 Increase Pull Downwards
if (keys[VK_NUMPAD2] && (particle[loop].yg>-1.5f)) particle[loop].yg-=0.01f;
// If Number Pad 6 And X Gravity Is Less Than 1.5 Increase Pull Right
if (keys[VK_NUMPAD6] && (particle[loop].xg<1.5f)) particle[loop].xg+=0.01f;
// If Number Pad 4 And X Gravity Is Greater Than -1.5 Increase Pull Left
if (keys[VK_NUMPAD4] && (particle[loop].xg>-1.5f)) particle[loop].xg-=0.01f;
if (keys[VK_TAB]) // Tab Key Causes A Burst
{
particle[loop].x=0.0f; // Center On X Axis
particle[loop].y=0.0f; // Center On Y Axis
particle[loop].z=0.0f; // Center On Z Axis
particle[loop].xi=float((rand()%50)-26.0f)*10.0f; // Random Speed On X Axis
particle[loop].yi=float((rand()%50)-25.0f)*10.0f; // Random Speed On Y Axis
particle[loop].zi=float((rand()%50)-25.0f)*10.0f; // Random Speed On Z Axis
}
}
}
return TRUE; // Everything Went OK
}//end
GLvoid KillGLWindow(GLvoid) // Properly Kill The Window
{
if (fullscreen) // Are We In Fullscreen Mode?
{
ChangeDisplaySettings(NULL,0); // If So Switch Back To The Desktop
ShowCursor(TRUE); // Show Mouse Pointer
}
if (hRC) // Do We Have A Rendering Context?
{
if (!wglMakeCurrent(NULL,NULL)) // Are We Able To Release The DC And RC Contexts?
{
MessageBox(NULL,_T("Release Of DC And RC Failed."),_T("SHUTDOWN ERROR"),MB_OK | MB_ICONINFORMATION);
}
if (!wglDeleteContext(hRC)) // Are We Able To Delete The RC?
{
MessageBox(NULL,_T("Release Rendering Context Failed."),_T("SHUTDOWN ERROR"),MB_OK | MB_ICONINFORMATION);
}
hRC=NULL; // Set RC To NULL
}
if (hDC && !ReleaseDC(hWnd,hDC)) // Are We Able To Release The DC
{
MessageBox(NULL,_T("Release Device Context Failed."),_T("SHUTDOWN ERROR"),MB_OK | MB_ICONINFORMATION);
hDC=NULL; // Set DC To NULL
}
if (hWnd && !DestroyWindow(hWnd)) // Are We Able To Destroy The Window?
{
MessageBox(NULL,_T("Could Not Release hWnd."),_T("SHUTDOWN ERROR"),MB_OK | MB_ICONINFORMATION);
hWnd=NULL; // Set hWnd To NULL
}
if (!UnregisterClass(_T("OpenGL"),hInstance)) // Are We Able To Unregister Class
{
MessageBox(NULL,_T("Could Not Unregister Class."),_T("SHUTDOWN ERROR"),MB_OK | MB_ICONINFORMATION);
hInstance=NULL; // Set hInstance To NULL
}
}//end of KillGLWindow
BOOL CreateGLWindow(TCHAR * title, int width, int height, int bits, bool fullscreenflag)
{
GLuint PixelFormat; // Holds The Results After Searching For A Match
WNDCLASS wc; // Windows Class Structure
DWORD dwExStyle; // Window Extended Style
DWORD dwStyle; // Window Style
RECT WindowRect; // Grabs Rectangle Upper Left / Lower Right Values
WindowRect.left=(long)0; // Set Left Value To 0
WindowRect.right=(long)width; // Set Right Value To Requested Width
WindowRect.top=(long)0; // Set Top Value To 0
WindowRect.bottom=(long)height; // Set Bottom Value To Requested Height
fullscreen=fullscreenflag; // Set The Global Fullscreen Flag
hInstance= GetModuleHandle(NULL); // Grab An Instance For Our Window
wc.style= CS_HREDRAW | CS_VREDRAW | CS_OWNDC; // Redraw On Move, And Own DC For Window
wc.lpfnWndProc = (WNDPROC) WndProc; // WndProc Handles Messages
wc.cbClsExtra = 0; // No Extra Window Data
wc.cbWndExtra = 0; // No Extra Window Data
wc.hInstance = hInstance; // Set The Instance
wc.hIcon = LoadIcon(NULL, IDI_WINLOGO); // Load The Default Icon
wc.hCursor = LoadCursor(NULL, IDC_ARROW); // Load The Arrow Pointer
wc.hbrBackground = NULL; // No Background Required For GL
wc.lpszMenuName = NULL; // We Don't Want A Menu
wc.lpszClassName = _T("OpenGL"); // Set The Class Name
if (!RegisterClass(&wc)) // Attempt To Register The Window Class
{
MessageBox(NULL,_T("Failed To Register The Window Class."),_T("ERROR"),MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Exit And Return FALSE
}
if (fullscreen) // Attempt Fullscreen Mode?
{
DEVMODE dmScreenSettings; // Device Mode
memset(&dmScreenSettings,0,sizeof(dmScreenSettings)); // Makes Sure Memory's Cleared
dmScreenSettings.dmSize = sizeof(dmScreenSettings); // Size Of The Devmode Structure
dmScreenSettings.dmPelsWidth = width; // Selected Screen Width
dmScreenSettings.dmPelsHeight = height; // Selected Screen Height
dmScreenSettings.dmBitsPerPel = bits; // Selected Bits Per Pixel
dmScreenSettings.dmFields=DM_BITSPERPEL|DM_PELSWIDTH|DM_PELSHEIGHT;
// Try To Set Selected Mode And Get Results. NOTE: CDS_FULLSCREEN Gets Rid Of Start Bar.
if (ChangeDisplaySettings(&dmScreenSettings,CDS_FULLSCREEN)!=DISP_CHANGE_SUCCESSFUL)
{
// If The Mode Fails, Offer Two Options. Quit Or Run In A Window.
if (MessageBox(NULL,_T("The Requested Fullscreen Mode Is Not Supported By\nYour Video Card. Use Windowed Mode Instead?"),_T("NeHe GL"),MB_YESNO|MB_ICONEXCLAMATION)==IDYES)
{
fullscreen=FALSE; // Select Windowed Mode (Fullscreen=FALSE)
}
else
{
// Pop Up A Message Box Letting User Know The Program Is Closing.
MessageBox(NULL,_T("Program Will Now Close."),_T("ERROR"),MB_OK|MB_ICONSTOP);
return FALSE; // Exit And Return FALSE
}
}
}
if (fullscreen) // Are We Still In Fullscreen Mode?
{
dwExStyle=WS_EX_APPWINDOW; // Window Extended Style
dwStyle=WS_POPUP; // Windows Style
ShowCursor(FALSE); // Hide Mouse Pointer
}
else
{
dwExStyle=WS_EX_APPWINDOW | WS_EX_WINDOWEDGE; // Window Extended Style
dwStyle=WS_OVERLAPPEDWINDOW; // Windows Style
}
AdjustWindowRectEx(&WindowRect, dwStyle, FALSE, dwExStyle); // Adjust Window To True Requested Size
if (!(hWnd=CreateWindowEx( dwExStyle, // Extended Style For The Window
_T("OpenGL"), // Class Name
title, // Window Title
WS_CLIPSIBLINGS | // Required Window Style
WS_CLIPCHILDREN | // Required Window Style
dwStyle, // Selected Window Style
0, 0, // Window Position
WindowRect.right-WindowRect.left, // Calculate Adjusted Window Width
WindowRect.bottom-WindowRect.top, // Calculate Adjusted Window Height
NULL, // No Parent Window
NULL, // No Menu
hInstance, // Instance
NULL))) // Don't Pass Anything To WM_CREATE
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,_T("Window Creation Error."),_T("ERROR"),MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
static PIXELFORMATDESCRIPTOR pfd= // pfd Tells Windows How We Want Things To Be
{
sizeof(PIXELFORMATDESCRIPTOR), // Size Of This Pixel Format Descriptor
1, // Version Number
PFD_DRAW_TO_WINDOW | // Format Must Support Window
PFD_SUPPORT_OPENGL | // Format Must Support OpenGL
PFD_DOUBLEBUFFER, // Must Support Double Buffering
PFD_TYPE_RGBA, // Request An RGBA Format
bits, // Select Our Color Depth
0, 0, 0, 0, 0, 0, // Color Bits Ignored
0, // No Alpha Buffer
0, // Shift Bit Ignored
0, // No Accumulation Buffer
0, 0, 0, 0, // Accumulation Bits Ignored
16, // 16Bit Z-Buffer (Depth Buffer)
0, // No Stencil Buffer
0, // No Auxiliary Buffer
PFD_MAIN_PLANE, // Main Drawing Layer
0, // Reserved
0, 0, 0 // Layer Masks Ignored
};
if (!(hDC=GetDC(hWnd))) // Did We Get A Device Context?
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,_T("Can't Create A GL Device Context."),_T("ERROR"),MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
if (!(PixelFormat=ChoosePixelFormat(hDC,&pfd))) // Did Windows Find A Matching Pixel Format?
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,_T("Can't Find A Suitable PixelFormat."),_T("ERROR"),MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
if(!SetPixelFormat(hDC,PixelFormat,&pfd)) // Are We Able To Set The Pixel Format?
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,_T("Can't Set The PixelFormat."),_T("ERROR"),MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
if (!(hRC=wglCreateContext(hDC))) // Are We Able To Get A Rendering Context?
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,_T("Can't Create A GL Rendering Context."),_T("ERROR"),MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
if(!wglMakeCurrent(hDC,hRC)) // Try To Activate The Rendering Context
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,_T("Can't Activate The GL Rendering Context."),_T("ERROR"),MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
ShowWindow(hWnd,SW_SHOW); // Show The Window
SetForegroundWindow(hWnd); // Slightly Higher Priority
SetFocus(hWnd); // Sets Keyboard Focus To The Window
ReSizeGLScene(width, height); // Set Up Our Perspective GL Screen
if (!InitGL()) // Initialize Our Newly Created GL Window
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,_T("Initialization Failed."),_T("ERROR"),MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
return TRUE; // Success
}//end of CreateGLWindow
LRESULT CALLBACK WndProc( HWND hWnd, // Handle For This Window
UINT uMsg, // Message For This Window
WPARAM wParam, // Additional Message Information
LPARAM lParam) // Additional Message Information
{
switch (uMsg) // Check For Windows Messages
{
case WM_ACTIVATE: // Watch For Window Activate Message
{
if (!HIWORD(wParam)) // Check Minimization State
{
active=TRUE; // Program Is Active
}
else
{
active=FALSE; // Program Is No Longer Active
}
return 0; // Return To The Message Loop
}
case WM_SYSCOMMAND: // Intercept System Commands
{
switch (wParam) // Check System Calls
{
case SC_SCREENSAVE: // Screensaver Trying To Start?
case SC_MONITORPOWER: // Monitor Trying To Enter Powersave?
return 0; // Prevent From Happening
}
break; // Exit
}
case WM_CLOSE: // Did We Receive A Close Message?
{
PostQuitMessage(0); // Send A Quit Message
return 0; // Jump Back
}
case WM_KEYDOWN: // Is A Key Being Held Down?
{
keys[wParam] = TRUE; // If So, Mark It As TRUE
return 0; // Jump Back
}
case WM_KEYUP: // Has A Key Been Released?
{
keys[wParam] = FALSE; // If So, Mark It As FALSE
return 0; // Jump Back
}
case WM_SIZE: // Resize The OpenGL Window
{
ReSizeGLScene(LOWORD(lParam),HIWORD(lParam)); // LoWord=Width, HiWord=Height
return 0; // Jump Back
}
}
// Pass All Unhandled Messages To DefWindowProc
return DefWindowProc(hWnd,uMsg,wParam,lParam);
}//end of WndProc
int WINAPI WinMain( HINSTANCE hInstance, // Instance
HINSTANCE hPrevInstance, // Previous Instance
LPSTR lpCmdLine, // Command Line Parameters
int nCmdShow) // Window Show State
{
MSG msg; // Windows Message Structure
BOOL done=FALSE; // Bool Variable To Exit Loop
// Ask The User Which Screen Mode They Prefer
if (MessageBox(NULL,_T("Would You Like To Run In Fullscreen Mode?"), _T("Start FullScreen?"),MB_YESNO|MB_ICONQUESTION)==IDNO)
{
fullscreen=FALSE; // Windowed Mode
}
// Create Our OpenGL Window
if (!CreateGLWindow(_T("NeHe's Particle Tutorial"),640,480,16,fullscreen))
{
return 0; // Quit If Window Was Not Created
}
if (fullscreen) // Are We In Fullscreen Mode ( ADD )
{
slowdown=1.0f; // Speed Up The Particles (3dfx Issue) ( ADD )
}
while(!done) // Loop That Runs Until done=TRUE
{
if (PeekMessage(&msg,NULL,0,0,PM_REMOVE)) // Is There A Message Waiting?
{
if (msg.message==WM_QUIT) // Have We Received A Quit Message?
{
done=TRUE; // If So done=TRUE
}
else // If Not, Deal With Window Messages
{
TranslateMessage(&msg); // Translate The Message
DispatchMessage(&msg); // Dispatch The Message
}
}
else // If There Are No Messages
{
if ((active && !DrawGLScene()) || keys[VK_ESCAPE]) // Updating View Only If Active
{
done=TRUE; // ESC or DrawGLScene Signalled A Quit
}
else // Not Time To Quit, Update Screen
{
SwapBuffers(hDC); // Swap Buffers (Double Buffering)
if (keys[VK_ADD] && (slowdown>1.0f)) slowdown-=0.01f; // Speed Up Particles
if (keys[VK_SUBTRACT] && (slowdown<4.0f)) slowdown+=0.01f; // Slow Down Particles
if (keys[VK_PRIOR]) zoom+=0.1f; // Zoom In
if (keys[VK_NEXT]) zoom-=0.1f; // Zoom Out
if (keys[VK_RETURN] && !rp) // Return Key Pressed
{
rp=true; // Set Flag Telling Us It's Pressed
rainbow=!rainbow; // Toggle Rainbow Mode On / Off
}
if (!keys[VK_RETURN]) rp=false; // If Return Is Released Clear Flag
if ((keys[' '] && !sp) || (rainbow && (delay>25))) // Space Or Rainbow Mode
{
if (keys[' ']) rainbow=false; // If Spacebar Is Pressed Disable Rainbow Mode
sp=true; // Set Flag Telling Us Space Is Pressed
delay=0; // Reset The Rainbow Color Cycling Delay
col++; // Change The Particle Color
if (col>11) col=0; // If Color Is To High Reset It
}
if (!keys[' ']) sp=false; // If Spacebar Is Released Clear Flag
// If Up Arrow And Y Speed Is Less Than 200 Increase Upward Speed
if (keys[VK_UP] && (yspeed<200)) yspeed+=1.0f;
// If Down Arrow And Y Speed Is Greater Than -200 Increase Downward Speed
if (keys[VK_DOWN] && (yspeed>-200)) yspeed-=1.0f;
// If Right Arrow And X Speed Is Less Than 200 Increase Speed To The Right
if (keys[VK_RIGHT] && (xspeed<200)) xspeed+=1.0f;
// If Left Arrow And X Speed Is Greater Than -200 Increase Speed To The Left
if (keys[VK_LEFT] && (xspeed>-200)) xspeed-=1.0f;
delay++; // Increase Rainbow Mode Color Cycling Delay Counter
if (keys[VK_F1]) // Is F1 Being Pressed?
{
keys[VK_F1]=FALSE; // If So Make Key FALSE
KillGLWindow(); // Kill Our Current Window
fullscreen=!fullscreen; // Toggle Fullscreen / Windowed Mode
// Recreate Our OpenGL Window
if (!CreateGLWindow(_T("NeHe's Particle Tutorial"),640,480,16,fullscreen))
{
return 0; // Quit If Window Was Not Created
}
}
}
}
}
// Shutdown
KillGLWindow(); // Kill The Window
return (msg.wParam); // Exit The Program
}
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