94 lines
3.5 KiB
Rust
94 lines
3.5 KiB
Rust
// Copyright 2013-2014 The CGMath Developers. For a full listing of the authors,
|
|
// refer to the AUTHORS file at the top-level directory of this distribution.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
//! View frustum for visibility determination
|
|
|
|
use array::Array2;
|
|
use bound::*;
|
|
use matrix::Matrix4;
|
|
use num::BaseFloat;
|
|
use plane::Plane;
|
|
use point::Point3;
|
|
use vector::{Vector, EuclideanVector};
|
|
|
|
#[derive(Copy, Clone, Debug, PartialEq, RustcEncodable, RustcDecodable)]
|
|
pub struct Frustum<S: BaseFloat> {
|
|
pub left: Plane<S>,
|
|
pub right: Plane<S>,
|
|
pub bottom: Plane<S>,
|
|
pub top: Plane<S>,
|
|
pub near: Plane<S>,
|
|
pub far: Plane<S>,
|
|
}
|
|
|
|
impl<S: BaseFloat + 'static>
|
|
Frustum<S> {
|
|
/// Construct a frustum.
|
|
pub fn new(left: Plane<S>, right: Plane<S>,
|
|
bottom: Plane<S>, top: Plane<S>,
|
|
near: Plane<S>, far: Plane<S>) -> Frustum<S> {
|
|
Frustum {
|
|
left: left,
|
|
right: right,
|
|
bottom: bottom,
|
|
top: top,
|
|
near: near,
|
|
far: far,
|
|
}
|
|
}
|
|
|
|
/// Extract frustum planes from a projection matrix.
|
|
pub fn from_matrix4(mat: Matrix4<S>) -> Option<Frustum<S>> {
|
|
Some(Frustum::new(
|
|
match Plane::from_vector4_alt(mat.row(3).add_v(&mat.row(0))).normalize()
|
|
{ Some(p) => p, None => return None },
|
|
match Plane::from_vector4_alt(mat.row(3).sub_v(&mat.row(0))).normalize()
|
|
{ Some(p) => p, None => return None },
|
|
match Plane::from_vector4_alt(mat.row(3).add_v(&mat.row(1))).normalize()
|
|
{ Some(p) => p, None => return None },
|
|
match Plane::from_vector4_alt(mat.row(3).sub_v(&mat.row(1))).normalize()
|
|
{ Some(p) => p, None => return None },
|
|
match Plane::from_vector4_alt(mat.row(3).add_v(&mat.row(2))).normalize()
|
|
{ Some(p) => p, None => return None },
|
|
match Plane::from_vector4_alt(mat.row(3).sub_v(&mat.row(2))).normalize()
|
|
{ Some(p) => p, None => return None }
|
|
))
|
|
}
|
|
|
|
/// Find the spatial relation of a bound inside this frustum.
|
|
pub fn contains<B: Bound<S>>(&self, bound: &B) -> Relation {
|
|
[&self.left, &self.right, &self.top, &self.bottom, &self.near, &self.far]
|
|
.iter().fold(Relation::In, |cur, p| {
|
|
use std::cmp::max;
|
|
let r = bound.relate_plane(p);
|
|
// If any of the planes are `Out`, the bound is outside.
|
|
// Otherwise, if any are `Cross`, the bound is crossing.
|
|
// Otherwise, the bound is fully inside.
|
|
max(cur, r)
|
|
})
|
|
}
|
|
}
|
|
|
|
#[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable)]
|
|
pub struct FrustumPoints<S> {
|
|
pub near_top_left: Point3<S>,
|
|
pub near_top_right: Point3<S>,
|
|
pub near_bottom_left: Point3<S>,
|
|
pub near_bottom_right: Point3<S>,
|
|
pub far_top_left: Point3<S>,
|
|
pub far_top_right: Point3<S>,
|
|
pub far_bottom_left: Point3<S>,
|
|
pub far_bottom_right: Point3<S>,
|
|
}
|