Quantize light frustum calculations (#12357)

* Quantize light frustum calculations

Reduces shadow flicker

* Fix function name to match conventions
master
x2048 2022-05-23 23:45:18 +02:00 committed by GitHub
parent 16a30556df
commit ed26ed5a1f
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 19 additions and 1 deletions

View File

@ -27,10 +27,24 @@ with this program; if not, write to the Free Software Foundation, Inc.,
using m4f = core::matrix4;
static v3f quantizeDirection(v3f direction, float step)
{
float yaw = std::atan2(direction.Z, direction.X);
float pitch = std::asin(direction.Y); // assume look is normalized
yaw = std::floor(yaw / step) * step;
pitch = std::floor(pitch / step) * step;
return v3f(std::cos(yaw)*std::cos(pitch), std::sin(pitch), std::sin(yaw)*std::cos(pitch));
}
void DirectionalLight::createSplitMatrices(const Camera *cam)
{
const float DISTANCE_STEP = BS * 2.0; // 2 meters
v3f newCenter;
v3f look = cam->getDirection();
look = quantizeDirection(look, M_PI / 12.0); // 15 degrees
// camera view tangents
float tanFovY = tanf(cam->getFovY() * 0.5f);
@ -42,6 +56,10 @@ void DirectionalLight::createSplitMatrices(const Camera *cam)
// adjusted camera positions
v3f cam_pos_world = cam->getPosition();
cam_pos_world = v3f(
floor(cam_pos_world.X / DISTANCE_STEP) * DISTANCE_STEP,
floor(cam_pos_world.Y / DISTANCE_STEP) * DISTANCE_STEP,
floor(cam_pos_world.Z / DISTANCE_STEP) * DISTANCE_STEP);
v3f cam_pos_scene = v3f(cam_pos_world.X - cam->getOffset().X * BS,
cam_pos_world.Y - cam->getOffset().Y * BS,
cam_pos_world.Z - cam->getOffset().Z * BS);
@ -61,7 +79,7 @@ void DirectionalLight::createSplitMatrices(const Camera *cam)
v3f boundVec = (cam_pos_scene + farCorner * sfFar) - center_scene;
float radius = boundVec.getLength();
float length = radius * 3.0f;
v3f eye_displacement = direction * length;
v3f eye_displacement = quantizeDirection(direction, M_PI / 2880 /*15 seconds*/) * length;
// we must compute the viewmat with the position - the camera offset
// but the future_frustum position must be the actual world position