   Slow speed when camera nears to the model
  i have create a simple program that contains a box with texture, when i move far away from the box then everything works smooth but as i come near to the model box , my movement became stucky, i think fps gets too much low at that time... why is this happening ? is there anyway to make it fine?below is my source// Gl_Engine.cpp: implementation of the Gl_Engine class.////////////////////////////////////////////////////////////////////////#include "Gl_Engine.h"#include <stdio.h>#include <math.h>//////////////////////////////////////////////////////////////////////// Construction/Destruction//////////////////////////////////////////////////////////////////////Gl_Engine::Gl_Engine(){m_hRC=NULL;m_RotDeg =m_RotDeg2 = 10;}Gl_Engine::~Gl_Engine(){}int Gl_Engine::InitGL(GLvoid){// Enables Smooth ShadingglClearColor(0.0f, 0.0f, 0.0f, 0.0f);// Black BackgroundglClearDepth(1.0f);// Depth Buffer SetupglEnable(GL_DEPTH_TEST);// Enables Depth TestingglDepthFunc(GL_LESS);// The Type Of Depth Test To DoglShadeModel(GL_SMOOTH);glEnable(GL_TEXTURE_2D); // Enable Texture Mapping ( NEW )glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);// Really Nice Perspective CalculationsStrArray tmpvar;tmpvar.push_back("C:\\Kasamba clinets\\OpenGlScene\\Textures\\NeHe.bmp");LoadTexture(tmpvar);//AddLight();return TRUE;// Initialization Went OK}int Gl_Engine::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//glDisable(GL_LIGHTING);glLoadIdentity();// Reset The Current Modelview MatrixRotateWorldObjects();SetWorldObjectDirection();// Reset The Current Modelview MatrixBuild3dHouse();//Sleep(30);return TRUE;// Everything Went OK }int Gl_Engine::CreateGlContext(HDC &r_hdc){if (!(m_hRC=wglCreateContext(r_hdc)))// Are We Able To Get A Rendering Context?{MessageBox(NULL,"Can't Create A GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;// Return FALSE}if(!wglMakeCurrent(r_hdc,m_hRC))// Try To Activate The Rendering Context{MessageBox(NULL,"Can't Activate The GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);return FALSE;// Return FALSE}return TRUE;}void Gl_Engine::CloseGl_Engine(){if (!wglMakeCurrent(NULL,NULL))// Are We Able To Release The DC And RC Contexts?{MessageBox(NULL,"Release Of DC And RC Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);}if (!wglDeleteContext(m_hRC))// Are We Able To Delete The RC?{MessageBox(NULL,"Release Rendering Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);}this->m_hRC=NULL;}void Gl_Engine::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 ViewportglMatrixMode(GL_PROJECTION);// Select The Projection MatrixglLoadIdentity();// Reset The Projection Matrix// Calculate The Aspect Ratio Of The WindowgluPerspective(45.0f,(GLfloat)width/(GLfloat)height,0.1f,100.0f);glMatrixMode(GL_MODELVIEW);// Select The Modelview MatrixglLoadIdentity();// Reset The Modelview Matrix}int Gl_Engine::LoadTexture(StrArray strFileNames){int iSize = strFileNames.size();if(iSize<1){return 0;}memset(TextureImage,0,sizeof(void *)*10); //for(int Loop=0; Loop<iSize; Loop++){if(LoadBMPS((char*)strFileNames[Loop].c_str(),TextureImage[0])==FALSE){string strTmp = "Problem in loading file from ";strTmp+=strFileNames[Loop].c_str();MessageBox(NULL,strTmp.c_str(),"Error",MB_OK);}glGenTextures(iSize, &m_Texture[Loop]); // Create The Texture// Typical Texture Generation Using Data From The BitmapglBindTexture(GL_TEXTURE_2D, m_Texture[Loop]);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); // Linear FilteringglTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR); // Linear FilteringglTexImage2D(GL_TEXTURE_2D, 0, 3, TextureImage[Loop]->sizeX, TextureImage[Loop]->sizeY, 0, GL_RGB,GL_UNSIGNED_BYTE, TextureImage[Loop]->data);/*glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_NEAREST);gluBuild2DMipmaps(GL_TEXTURE_2D, 3, TextureImage[Loop]->sizeX, TextureImage[Loop]->sizeY, GL_RGB,GL_UNSIGNED_BYTE, TextureImage[Loop]->data); */}    for(int Loop2=0; Loop2<iSize; Loop2++){if (TextureImage[Loop2]) // If Texture Exists{if (TextureImage[Loop2]->data) // If Texture Image Exists{free(TextureImage[Loop2]->data); // Free The Texture Image Memory}free(TextureImage[Loop2]); // Free The Image Structure}}return 1;}BOOL Gl_Engine::LoadBMPS(char *szFileName, AUX_RGBImageRec *&r_RGBrec){FILE *pfile=NULL;if(!szFileName){return FALSE;}pfile= fopen(szFileName,"r");if(!pfile){return FALSE;}else{ fclose(pfile); //it was just used to check it if file exist or not AUX_RGBImageRec *Tmp_RGBrec= auxDIBImageLoad(szFileName); r_RGBrec= Tmp_RGBrec;}return TRUE;}int Gl_Engine::AddLight(){GLfloat fLightAmb[]={0.5f,0.5f,0.5f,1.0f};GLfloat fLightDiffuse[]={1.0f,1.0f,1.0f,1.0f};GLfloat fLightPosition[]={0.0f,0.0f,2.0f,0.0f};glLightfv(GL_LIGHT1,GL_AMBIENT,fLightAmb);glLightfv(GL_LIGHT1,GL_DIFFUSE,fLightDiffuse);glLightfv(GL_LIGHT1,GL_POSITION,fLightPosition);glEnable(GL_LIGHTING);glEnable(GL_LIGHT1);return 1;}void Gl_Engine::CameraMoveLeft(){m_Camera.fYRot += 1.5f;}void Gl_Engine::CameraMoveRight(){m_Camera.fYRot -= 1.5f;}void Gl_Engine::CameraMoveForward(){float fRad = PIOVER;m_Camera.fX -= (float)sin(m_Camera.fYRot * fRad) * 1.05f;m_Camera.fZ -= (float)cos(m_Camera.fYRot * fRad) * 1.05f;}void Gl_Engine::CameraMoveBackward(){float fRad = PIOVER;m_Camera.fX += (float)sin(m_Camera.fYRot * fRad) * 1.05f;m_Camera.fZ += (float)cos(m_Camera.fYRot * fRad) * 1.05f;}void Gl_Engine::RotateWorldObjects(){GLfloat sceneroty = 360.0f - m_Camera.fYRot;glRotatef(sceneroty,0,1.0f,0);}void Gl_Engine::SetWorldObjectDirection(){GLfloat worldx,worldy,worldz;worldx= -m_Camera.fX;worldz = -m_Camera.fZ;worldy = -0.25f;glTranslatef(worldx,worldy,worldz);}void Gl_Engine::Build3dHouse(){//it is necessary to off the debth buffer for blending effects glColor4f(1.0f,1.0f,1.0f,0.5f);//Blend the object glTranslatef(0.5f,0.0f,0.0f); // Move Right 3 Units//glRotatef(m_RotDeg2--,0.0f,1.0f,0.0f);glBindTexture(GL_TEXTURE_2D, m_Texture[0]); // Select Our TextureglBegin(GL_QUADS); // Draw A Quad//Front.glNormal3f(0.0f,0.0f,1.0f);glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and QuadglTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and QuadglTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f); // Top Right Of The Texture and QuadglTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f); // Top Left Of The Texture and Quad// Back FaceglNormal3f(0.0f,0.0f,-1.0f);glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f); // Bottom Right Of The Texture andQuadglTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); // Top Right Of The Texture and QuadglTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); // Top Left Of The Texture and QuadglTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f); // Bottom Left Of The Texture and Quad// Top FaceglNormal3f(0.0f,1.0f,0.0f);glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); // Top Left Of The Texture and QuadglTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, 1.0f, 1.0f); // Bottom Left Of The Texture and QuadglTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, 1.0f, 1.0f); // Bottom Right Of The Texture and QuadglTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); // Top Right Of The Texture and Quad// Bottom FaceglNormal3f(0.0f,1.0f,0.0f);glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f); // Top Right Of The Texture and QuadglTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f); // Top Left Of The Texture and QuadglTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and QuadglTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and Quad// Right faceglNormal3f(1.0f,0.0f,0.0f);glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f); // Bottom Right Of The Texture and QuadglTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); // Top Right Of The Texture and QuadglTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f); // Top Left Of The Texture and QuadglTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and Quad// Left FaceglNormal3f(-1.0f,0.0f,0.0f);glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f); // Bottom Left Of The Texture and QuadglTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and QuadglTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f); // Top Right Of The Texture and QuadglTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); // Top Left Of The Texture and QuadglEnd();//glDisable(GL_TEXTURE_2D); // Enable Texture Mapping ( NEW )}
  sounds like your app is fillrate limited.  try looking up the latest drivers for your video card (they may add extra hardware acceleration support).  other than that, build mipmaps (you have it commented out in your code).a few other things to help if you have to live in software mode: disable blending, enable back face culling and use a display list to draw your house.   