// This runs once every physics timestep.
void update(float dt)
{
// This section just checks to make sure the object stays within a certain boundary. This is not really collision detection.
glm::vec3 tempPos = obj2->GetPosition();
if (fabsf(tempPos.x) > 0.9f)
{
glm::vec3 tempVel = obj2->GetVelocity();
// "Bounce" the velocity along the axis that was over-extended.
obj2->SetVelocity(glm::vec3(-1.0f * tempVel.x, tempVel.y, tempVel.z));
}
if (fabsf(tempPos.y) > 0.8f)
{
glm::vec3 tempVel = obj2->GetVelocity();
obj2->SetVelocity(glm::vec3(tempVel.x, -1.0f * tempVel.y, tempVel.z));
}
// Rotate the objects if you'd like, this will show you how the AABB stays aligned on the X and Y axes regardless of the object's orientation.
//obj1->Rotate(glm::vec3(glm::radians(0.0f), glm::radians(0.0f), glm::radians(1.0f)));
//obj2->Rotate(glm::vec3(glm::radians(0.0f), glm::radians(0.0f), glm::radians(1.0f)));
// Re-calculate the Axis-Aligned Bounding Box for your object.
// We do this because if the object's orientation changes, we should update the bounding box as well.
// Be warned: For some objects this can actually cause a collision to be missed, so be careful.
// (This is because we determine the time of the collision based on the AABB, but if the AABB changes significantly, the time of collision can change between frames,
// and if that lines up just right you'll miss the collision altogether.)
obj1->CalculateAABB();
obj2->CalculateAABB();
if (TestAABB(obj1->GetAABB(), obj2->GetAABB()))
{
// Create a local velocity variable based off of the moving object's velocity.
glm::vec3 velocity = obj2->GetVelocity();
// Reverse the velocity in the x direction
// This is the "bounce" effect, only we don't actually know the axis of collision from the test. Instead, we assume it because the object is only moving in the x
// direction.
velocity.x *= -1;
obj2->SetVelocity(velocity);
}
obj1->Update(dt);
obj2->Update(dt);
// Update your MVP matrices based on the objects' transforms.
MVP = PV * *obj1->GetTransform();
MVP2 = PV * *obj2->GetTransform();
}
bool TestObjects(Object* O1, Object* O2){
//Determine which algorithm we need
int Complexity;
if(O1->GetComplexity() > O2->GetComplexity()){
Complexity = O1->GetComplexity();
}else{
Complexity = O2->GetComplexity();
}
//use the appropriate algorithm
bool collision = false;
if(Complexity == COMP_AABB){
//typecast to our more specific AABB structure.
collision = TestAABB((AABB*)O1, (AABB*)O2);
}
return collision;
}
