void drawScene() {
glPushMatrix();
//Set the animation control variables.
if (!paused) frame++;
int ticks = frame % 1440;
if (frame % 1440 == 0) {
ticks = 0;
//Reset animation object positions and rotations.
planePriorX = 0, planePriorY = 0, planePriorZ = 0;
planePostX = 0, planePostY = 0, planePostZ = 0;
planeRotX = 0, planeRotY = 0, planeRotZ = 0;
eaglePriorX = -0.5, eaglePriorY = 0.03, eaglePriorZ = -0.1;
eaglePostX = 0, eaglePostY = 0, eaglePostZ = 0;
eagleRotX = 0, eagleRotY = 0, eagleRotZ = 0;
}
//Apply scene transformations.
glRotatef(30, 0, 1, 0);
glTranslatef(0, 0, -1500 * frame * SCALE_FACTOR);
//Make sure angles are in bounds.
bounds(planeRotX); bounds(planeRotY); bounds(planeRotZ);
bounds(eagleRotX); bounds(eagleRotY); bounds(eagleRotZ);
if (!paused) {
//Airplane transformation events.
//Constant swaying.
planeRotZ -= 0.5 * cos(ticks * 2 * PI / 180);
planePostY -= 0.01 * cos(ticks * PI / 180);
//Spin upside-down.
if (ticks >= 180 && ticks < 360) planeRotZ -= PI * 0.5 * sin(ticks * PI / 180);
//Spin back round.
if (ticks >= 360 && ticks < 540) planeRotZ += PI * 0.5 * sin(ticks * PI / 180);
//Dive.
if (ticks >= 720 && ticks < 900) {
planeRotX -= 0.25 * PI * sin(ticks * 2 * PI / 180);
planePriorY -= 0.005 * PI * sin(ticks * PI / 180);
planePriorZ -= 0.01 * PI * sin(ticks * 0.5 * PI / 180);
}
//Loop-the-loop
if (ticks >= 900 && ticks < 1220) {
planeRotX += 1;
planePriorY += 0.015 * PI * sin((ticks - 180) * PI / 180);
planePriorZ -= 0.015 * PI * cos((ticks - 180) * PI / 180);
}
//Reset position.
if (ticks >= 1220 && ticks < 1440) {
// These values were found by minimising errors using binary division.
planeRotX -= 0.1262345 * PI * sin(ticks * PI / 180);
planePriorY -= 0.002379563 * PI * sin(ticks * 0.5 * PI / 180);
planePriorZ -= 0.003826425 * PI * sin(ticks * 0.5 * PI / 180);
}
//Eagle transformation events.
//Set default position.
eaglePriorX = -1;
eaglePriorZ = 0.4;
//Set start position over left wing.
if (ticks >= 0 && ticks < 180) {
eaglePriorX = -0.5;
eaglePriorY = 0.03;
eaglePriorZ = -0.1;
}
//Move a little with the wing.
if (ticks >= 0 && ticks < 90) {
eagleRotZ -= cos(ticks * 2 * PI / 180);
eaglePostY -= 0.009 * sin(ticks * 2 * PI / 180);
}
//Move back, up and left.
if (ticks >= 90 && ticks < 180) {
eaglePriorX -= (float)0.5 / 90 * (ticks - 90);
eaglePriorZ += (float)0.5 / 90 * (ticks - 90);
eaglePostY += 0.009 * sin((ticks - 90) * 2 * PI / 180);
}
//Swaying.
if (ticks >= 90 && ticks < 1350) {
eagleRotZ -= 0.6 * cos((ticks + 90) * PI / 180);
eaglePostY -= 0.01 * cos((ticks + 90) * 2 * PI / 180);
}
//Avoid plane collision.
if (ticks >= 360 && ticks < 540) eagleRotZ += 0.25 * PI * sin(ticks * 2 * PI / 180);
//Glide from side to side.
if (ticks >= 720 && ticks < 1080) eaglePriorX += 0.4 * PI * sin(ticks * 0.5 * PI / 180);
//Move back to start position.
if (ticks >= 1350 && ticks < 1440) {
eaglePriorX += (float)0.5 / 90 * (ticks - 1350);
eaglePriorZ -= (float)0.5 / 90 * (ticks - 1350);
}
//Avoid plane collision.
if (ticks >= 1400 && ticks < 1420) eaglePriorY += 0.01;
if (ticks >= 1420 && ticks < 1440) eaglePriorY -= 0.01;
}
//Apply the transformations then draw the airplane.
glPushMatrix();
glTranslatef(planePriorX, planePriorY, planePriorZ);
glRotatef(planeRotX, 1, 0, 0);
glRotatef(planeRotY, 0, 1, 0);
glRotatef(planeRotZ, 0, 0, 1);
glTranslatef(planePostX, planePostY, planePostZ);
drawAirplane();
glPopMatrix();
//Apply the transformations then draw the eagle.
glPushMatrix();
glTranslatef(eaglePriorX, eaglePriorY, eaglePriorZ);
glRotatef(eagleRotX, 1, 0, 0);
glRotatef(eagleRotY, 0, 1, 0);
glRotatef(eagleRotZ, 0, 0, 1);
glTranslatef(eaglePostX, eaglePostY, eaglePostZ);
drawEagle();
glPopMatrix();
glPopMatrix();
}
void redraw(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
/* Only need this if you care to look at the stencil buffer */
if(dataChoice == STENCIL)
glClear(GL_STENCIL_BUFFER_BIT);
glPushMatrix();
glScalef(.5, .5, .5);
if(stage == 1)
goto doneWithFrame;
setupLight();
setupNormalDrawingState();
glPushMatrix();
glTranslatef(0, 1, 4);
glRotatef(135, 0, 1, 0);
drawAirplane();
glPopMatrix();
if(stage == 2)
goto doneWithFrame;
setupBasePolygonState(3); /* 2 decals */
drawGround();
if(stage == 3)
goto doneWithFrame;
setupDecalState(1); /* decal # 1 = the runway asphalt */
drawAsphalt();
if(stage == 4)
goto doneWithFrame;
setupDecalState(2); /* decal # 2 = yellow paint on the runway */
drawStripes();
if(stage == 5)
goto doneWithFrame;
setupDecalState(3); /* decal # 3 = the plane's shadow */
glDisable(GL_LIGHTING);
glEnable(GL_BLEND);
glPushMatrix();
glColor4f(0, 0, 0, .5);
glTranslatef(0, 0, 4);
glRotatef(135, 0, 1, 0);
glScalef(1, 0, 1);
drawAirplane();
glPopMatrix();
glDisable(GL_BLEND);
glEnable(GL_LIGHTING);
doneWithFrame:
setupNormalDrawingState();
glPopMatrix();
switch(dataChoice) {
case COLOR:
break; /* color already in back buffer */
case STENCIL:
copyStencilToColor(GL_BACK);
break;
case DEPTH:
copyDepthToColor(GL_BACK);
break;
}
glutSwapBuffers();
}