//Perform per-frame updates
void UpdateFrame()
{
//set currentTime and timePassed
static double lastTime=timer.GetTime();
double currentTime=timer.GetTime();
double timePassed=currentTime-lastTime;
lastTime=currentTime;
//Update window
WINDOW::Instance()->Update();
//Update the lights
for(int i=0; i<numLights; ++i)
{
lights[i].position+=lights[i].velocity*float(timePassed)/1000;
//bounce off the borders
if(lights[i].position.x>1.0f && lights[i].velocity.x>0.0f)
lights[i].velocity.x=-lights[i].velocity.x;
if(lights[i].position.x<-1.0f && lights[i].velocity.x<0.0f)
lights[i].velocity.x=-lights[i].velocity.x;
if(lights[i].position.z>1.0f && lights[i].velocity.z>0.0f)
lights[i].velocity.z=-lights[i].velocity.z;
if(lights[i].position.z<-1.0f && lights[i].velocity.z<0.0f)
lights[i].velocity.z=-lights[i].velocity.z;
}
//Toggle vertex program/fixed function
if(WINDOW::Instance()->IsKeyPressed('1') && GLEE_NV_vertex_program)
{
useVP1=true;
useVP2=false;
useFixedFunction=false;
}
if(WINDOW::Instance()->IsKeyPressed('2') && GLEE_NV_vertex_program2)
{
useVP1=false;
useVP2=true;
useFixedFunction=false;
}
if(WINDOW::Instance()->IsKeyPressed('3'))
{
useVP1=false;
useVP2=false;
useFixedFunction=true;
}
//Render frame
RenderFrame(currentTime, timePassed);
}
//Perform per-frame updates
void UpdateFrame()
{
//set currentTime and timePassed
static double lastTime=timer.GetTime();
double currentTime=timer.GetTime();
double timePassed=currentTime-lastTime;
lastTime=currentTime;
//Update window
WINDOW::Instance()->Update();
//Render frame
RenderFrame(currentTime, timePassed);
}
//draw a frame
void RenderFrame()
{
//Clear buffers
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity(); //reset modelview matrix
glEnable(GL_LIGHTING);
glTranslatef(0.0f, 0.0f, -30.0f);
glRotatef((float)timer.GetTime()/30, 1.0f, 0.0f, 1.0f);
cubeGrid.DrawSurface(threshold);
glDisable(GL_LIGHTING);
fpsCounter.Update(); //update frames per second counter
glColor4f(0.0f, 0.0f, 1.0f, 1.0f);
window.StartTextMode();
window.Print(0, 28, "FPS: %.2f", fpsCounter.GetFps()); //print the fps
glColor4f(1.0f, 1.0f, 0.0f, 1.0f);
window.Print(0, 48, "Grid Size: %d", gridSize);
window.Print(0, 68, "%d triangles drawn", cubeGrid.numFacesDrawn);
window.EndTextMode();
glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
if(window.isKeyPressed(VK_F1))
{
window.SaveScreenshot();
window.SetKeyReleased(VK_F1);
}
window.SwapBuffers(); //swap buffers
//check for any opengl errors
window.CheckGLError();
//quit if necessary
if(window.isKeyPressed(VK_ESCAPE))
PostQuitMessage(0);
}
//Perform per frame updates
void UpdateFrame(unsigned char key, int x, int y)
{
angle=(float)timer.GetTime()/25;
objectLightDirection=worldLightDirection.GetRotatedY(-angle);
objectViewDirection=worldViewDirection.GetRotatedY(-angle);
//update vertex program registers
//Light direction in c[4]
glProgramParameter4fvNV(GL_VERTEX_PROGRAM_NV, 4, VECTOR4D(objectLightDirection.GetNormalized()));
//view direction in c[5]
glProgramParameter4fvNV(GL_VERTEX_PROGRAM_NV, 5, VECTOR4D(objectViewDirection.GetNormalized()));
// //pause & unpause
// if(window.isKeyPressed('P'))
// timer.Pause();
//
// if(window.isKeyPressed('U'))
// timer.Unpause();
//
// //change technique
// if(window.isKeyPressed('1') && paths1And2Supported)
// currentTechnique=SINGLE_PASS;
//
// if(window.isKeyPressed('2') && paths1And2Supported)
// currentTechnique=TEXTURE_LOOKUP;
//
// if(window.isKeyPressed('3'))
// currentTechnique=FALLBACK;
//
// //toggle bumpy
// if(window.isKeyPressed('B'))
// showBumps=true;
//
// if(window.isKeyPressed('F'))
// showBumps=false;
}
//draw a frame
void RenderFrame()
{
//Draw to pbuffer
pbuffer.MakeCurrent();
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity(); //reset modelview matrix
gluLookAt( 0.0f, 0.0f, 4.0f,
0.0f, 0.0f, 0.0f,
0.0f, 1.0f, 0.0f);
//Draw scene
if(drawTextured)
{
glBindTexture(GL_TEXTURE_2D, decalTexture);
glEnable(GL_TEXTURE_2D);
glPushMatrix();
glRotatef(timer.GetTime()/20, 0.0f, 1.0f, 0.0f);
glutSolidTeapot(0.8f);
glPopMatrix();
glDisable(GL_TEXTURE_2D);
}
else
{
glPushMatrix();
glRotatef(timer.GetTime()/20, 0.0f, 1.0f, 0.0f);
glRotatef(55.0f, 1.0f, 0.0f, 0.0f);
glutWireTorus(0.3f, 1.0f, 12, 24);
glPopMatrix();
glPushMatrix();
glRotatef(timer.GetTime()/20, 0.0f, 1.0f, 0.0f);
glRotatef(-55.0f, 1.0f, 0.0f, 0.0f);
glutWireTorus(0.3f, 1.0f, 12, 24);
glPopMatrix();
}
//Draw to window
window.MakeCurrent();
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
camera.SetupViewMatrix();
glLoadMatrixf(camera.viewMatrix);
glBindTexture(GL_TEXTURE_2D, pbufferTexture);
//use the pbuffer as the texture
wglBindTexImageARB(pbuffer.hBuffer, WGL_FRONT_LEFT_ARB);
//Draw simple rectangle
glBegin(GL_TRIANGLE_STRIP);
{
glTexCoord2f(0.0f, 0.0f);
glVertex3f(-1.0f, -1.0f, 0.0f);
glTexCoord2f(0.0f, 1.0f);
glVertex3f(-1.0f, 1.0f, 0.0f);
glTexCoord2f(1.0f, 0.0f);
glVertex3f( 1.0f, -1.0f, 0.0f);
glTexCoord2f(1.0f, 1.0f);
glVertex3f( 1.0f, 1.0f, 0.0f);
}
glEnd();
//release the pbuffer for further rendering
wglReleaseTexImageARB(pbuffer.hBuffer, WGL_FRONT_LEFT_ARB);
fpsCounter.Update(); //update frames per second counter
glColor4f(1.0f, 1.0f, 0.0f, 1.0f);
window.StartTextMode();
window.Print(0, 28, "FPS: %.2f", fpsCounter.GetFps()); //print the fps
glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
window.Print(0, 48, "%dx Anisotropy", currentAnisotropy);
glColor4f(0.0f, 1.0f, 0.0f, 1.0f);
window.Print(0, 68, "%s", useMipmapFilter ? "LINEAR_MIPMAP_LINEAR filtering" :
"LINEAR filtering");
window.EndTextMode();
glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
if(window.isKeyPressed(VK_F1))
{
window.SaveScreenshot();
window.SetKeyReleased(VK_F1);
}
window.SwapBuffers(); //swap buffers
//check for any opengl errors
window.CheckGLError();
//quit if necessary
if(window.isKeyPressed(VK_ESCAPE))
PostQuitMessage(0);
}
//Called to draw scene
void Display(void)
{
//angle of spheres in scene. Calculate from time
float angle=timer.GetTime()/10;
//First pass - from light's point of view
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_PROJECTION);
glLoadMatrixf(lightProjectionMatrix);
glMatrixMode(GL_MODELVIEW);
glLoadMatrixf(lightViewMatrix);
//Use viewport the same size as the shadow map
glViewport(0, 0, shadowMapSize, shadowMapSize);
//Draw back faces into the shadow map
glCullFace(GL_FRONT);
//Disable color writes, and use flat shading for speed
glShadeModel(GL_FLAT);
glColorMask(0, 0, 0, 0);
//Draw the scene
DrawScene(angle);
//Read the depth buffer into the shadow map texture
glBindTexture(GL_TEXTURE_2D, shadowMapTexture);
glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, shadowMapSize, shadowMapSize);
//restore states
glCullFace(GL_BACK);
glShadeModel(GL_SMOOTH);
glColorMask(1, 1, 1, 1);
//2nd pass - Draw from camera's point of view
glClear(GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_PROJECTION);
glLoadMatrixf(cameraProjectionMatrix);
glMatrixMode(GL_MODELVIEW);
glLoadMatrixf(cameraViewMatrix);
glViewport(0, 0, windowWidth, windowHeight);
//Use dim light to represent shadowed areas
glLightfv(GL_LIGHT1, GL_POSITION, VECTOR4D(lightPosition));
glLightfv(GL_LIGHT1, GL_AMBIENT, white*0.2f);
glLightfv(GL_LIGHT1, GL_DIFFUSE, white*0.2f);
glLightfv(GL_LIGHT1, GL_SPECULAR, black);
glEnable(GL_LIGHT1);
glEnable(GL_LIGHTING);
DrawScene(angle);
//3rd pass
//Draw with bright light
glLightfv(GL_LIGHT1, GL_DIFFUSE, white);
glLightfv(GL_LIGHT1, GL_SPECULAR, white);
//Calculate texture matrix for projection
//This matrix takes us from eye space to the light's clip space
//It is postmultiplied by the inverse of the current view matrix when specifying texgen
static MATRIX4X4 biasMatrix(0.5f, 0.0f, 0.0f, 0.0f,
0.0f, 0.5f, 0.0f, 0.0f,
0.0f, 0.0f, 0.5f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f); //bias from [-1, 1] to [0, 1]
MATRIX4X4 textureMatrix=biasMatrix*lightProjectionMatrix*lightViewMatrix;
//MATRIX4X4 textureMatrix=lightProjectionMatrix*lightViewMatrix;
//Set up texture coordinate generation.
glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
glTexGenfv(GL_S, GL_EYE_PLANE, textureMatrix.GetRow(0));
glEnable(GL_TEXTURE_GEN_S);
glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
glTexGenfv(GL_T, GL_EYE_PLANE, textureMatrix.GetRow(1));
glEnable(GL_TEXTURE_GEN_T);
glTexGeni(GL_R, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
glTexGenfv(GL_R, GL_EYE_PLANE, textureMatrix.GetRow(2));
glEnable(GL_TEXTURE_GEN_R);
glTexGeni(GL_Q, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
glTexGenfv(GL_Q, GL_EYE_PLANE, textureMatrix.GetRow(3));
glEnable(GL_TEXTURE_GEN_Q);
//Bind & enable shadow map texture
glBindTexture(GL_TEXTURE_2D, shadowMapTexture);
glEnable(GL_TEXTURE_2D);
//Enable shadow comparison
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, GL_COMPARE_R_TO_TEXTURE);
//Shadow comparison should be true (ie not in shadow) if r<=texture
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC_ARB, GL_LEQUAL);
//Shadow comparison should generate an INTENSITY result
glTexParameteri(GL_TEXTURE_2D, GL_DEPTH_TEXTURE_MODE_ARB, GL_INTENSITY);
//Set alpha test to discard false comparisons
glAlphaFunc(GL_GEQUAL, 0.99f);
glEnable(GL_ALPHA_TEST);
DrawScene(angle);
//Disable textures and texgen
glDisable(GL_TEXTURE_2D);
glDisable(GL_TEXTURE_GEN_S);
glDisable(GL_TEXTURE_GEN_T);
glDisable(GL_TEXTURE_GEN_R);
glDisable(GL_TEXTURE_GEN_Q);
//Restore other states
glDisable(GL_LIGHTING);
glDisable(GL_ALPHA_TEST);
//Update frames per second counter
fpsCounter.Update();
//Print fps
static char fpsString[32];
sprintf(fpsString, "%.2f", fpsCounter.GetFps());
//Set matrices for ortho
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
gluOrtho2D(-1.0f, 1.0f, -1.0f, 1.0f);
glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glLoadIdentity();
//Print text
glRasterPos2f(-1.0f, 0.9f);
for(unsigned int i=0; i<strlen(fpsString); ++i)
glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, fpsString[i]);
//reset matrices
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
glPopMatrix();
glFinish();
glutSwapBuffers();
glutPostRedisplay();
}
//Perform per frame updates
void UpdateFrame()
{
window.Update();
//update balls' position
float c = 2.0f*(float)cos(timer.GetTime()/600);
metaballs[0].position.x=-4.0f*(float)cos(timer.GetTime()/700) - c;
metaballs[0].position.y=4.0f*(float)sin(timer.GetTime()/600) - c;
metaballs[1].position.x=5.0f*(float)sin(timer.GetTime()/400) + c;
metaballs[1].position.y=5.0f*(float)cos(timer.GetTime()/400) - c;
metaballs[2].position.x=-5.0f*(float)cos(timer.GetTime()/400) - 0.2f*(float)sin(timer.GetTime()/600);
metaballs[2].position.y=5.0f*(float)sin(timer.GetTime()/500) - 0.2f*(float)sin(timer.GetTime()/400);
//increase or decrease density
if(window.isKeyPressed(VK_UP) && gridSize<maxGridSize)
{
gridSize++;
cubeGrid.Init(gridSize);
}
if(window.isKeyPressed(VK_DOWN) && gridSize>minGridSize)
{
gridSize--;
cubeGrid.Init(gridSize);
}
//pause & unpause
if(window.isKeyPressed('P'))
{
timer.Pause();
}
if(window.isKeyPressed('U'))
{
timer.Unpause();
}
//clear the field
for(int i=0; i<cubeGrid.numVertices; i++)
{
cubeGrid.vertices[i].value=0.0f;
cubeGrid.vertices[i].normal.LoadZero();
}
//evaluate the scalar field at each point
VECTOR3D ballToPoint;
float squaredRadius;
VECTOR3D ballPosition;
float normalScale;
for(int i=0; i<numMetaballs; i++)
{
squaredRadius=metaballs[i].squaredRadius;
ballPosition=metaballs[i].position;
//VC++6 standard does not inline functions
//by inlining these maually, in this performance-critical area,
//almost a 100% increase in speed is found
for(int j=0; j<cubeGrid.numVertices; j++)
{
//ballToPoint=cubeGrid.vertices[j].position-ballPosition;
ballToPoint.x=cubeGrid.vertices[j].position.x-ballPosition.x;
ballToPoint.y=cubeGrid.vertices[j].position.y-ballPosition.y;
ballToPoint.z=cubeGrid.vertices[j].position.z-ballPosition.z;
//get squared distance from ball to point
//float squaredDistance=ballToPoint.GetSquaredLength();
float squaredDistance= ballToPoint.x*ballToPoint.x +
ballToPoint.y*ballToPoint.y +
ballToPoint.z*ballToPoint.z;
if(squaredDistance==0.0f)
squaredDistance=0.0001f;
//value = r^2/d^2
cubeGrid.vertices[j].value+=squaredRadius/squaredDistance;
//normal = (r^2 * v)/d^4
normalScale=squaredRadius/(squaredDistance*squaredDistance);
//cubeGrid.vertices[j].normal+=ballToPoint*normalScale;
cubeGrid.vertices[j].normal.x+=ballToPoint.x*normalScale;
cubeGrid.vertices[j].normal.y+=ballToPoint.y*normalScale;
cubeGrid.vertices[j].normal.z+=ballToPoint.z*normalScale;
}
}
//toggle wireframe
if(window.isKeyPressed('W'))
{
glPolygonMode(GL_FRONT, GL_LINE);
}
if(window.isKeyPressed('F'))
{
glPolygonMode(GL_FRONT, GL_FILL);
}
//Change color
if(window.isKeyPressed(VK_SPACE))
{
currentDiffuseColor++;
if(currentDiffuseColor==numDiffuseColors)
currentDiffuseColor=0;
glLightfv(GL_LIGHT1, GL_DIFFUSE, diffuseColors[currentDiffuseColor]);
window.SetKeyReleased(VK_SPACE);
}
}
