const Matrix3x4& Light::GetVolumeTransform(Camera* camera)
{
if (!node_)
return Matrix3x4::IDENTITY;
switch (lightType_)
{
case LIGHT_DIRECTIONAL:
{
Matrix3x4 quadTransform;
Vector3 near, far;
// Position the directional light quad in halfway between far & near planes to prevent depth clipping
camera->GetFrustumSize(near, far);
quadTransform.SetTranslation(Vector3(0.0f, 0.0f, (camera->GetNearClip() + camera->GetFarClip()) * 0.5f));
quadTransform.SetScale(Vector3(far.x_, far.y_, 1.0f)); // Will be oversized, but doesn't matter (gets frustum clipped)
volumeTransform_ = camera->GetEffectiveWorldTransform() * quadTransform;
break;
}
case LIGHT_SPOT:
{
float yScale = tanf(fov_ * M_DEGTORAD * 0.5f) * range_;
float xScale = aspectRatio_ * yScale;
volumeTransform_ = Matrix3x4(node_->GetWorldPosition(), node_->GetWorldRotation(), Vector3(xScale, yScale, range_));
}
break;
case LIGHT_POINT:
volumeTransform_ = Matrix3x4(node_->GetWorldPosition(), Quaternion::IDENTITY, range_);
break;
}
return volumeTransform_;
}
Matrix3x4 Light::GetFullscreenQuadTransform(Camera* camera)
{
Matrix3x4 quadTransform;
Vector3 near, far;
// Position the directional light quad in halfway between far & near planes to prevent depth clipping
camera->GetFrustumSize(near, far);
quadTransform.SetTranslation(Vector3(0.0f, 0.0f, (camera->GetNearClip() + camera->GetFarClip()) * 0.5f));
quadTransform.SetScale(Vector3(far.x_, far.y_, 1.0f)); // Will be oversized, but doesn't matter (gets frustum clipped)
return camera->GetEffectiveWorldTransform() * quadTransform;
}
