24 lines
868 B
Rust
24 lines
868 B
Rust
#![allow(unused_variables)]
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extern crate nalgebra as na;
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use na::{Perspective3, Point2, Point3, Unit};
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fn main() {
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let projection = Perspective3::new(800.0 / 600.0, 3.14 / 2.0, 1.0, 1000.0);
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let screen_point = Point2::new(10.0f32, 20.0);
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// Compute two points in clip-space.
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// "ndc" = normalized device coordinates.
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let near_ndc_point = Point3::new(screen_point.x / 800.0, screen_point.y / 600.0, -1.0);
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let far_ndc_point = Point3::new(screen_point.x / 800.0, screen_point.y / 600.0, 1.0);
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// Unproject them to view-space.
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let near_view_point = projection.unproject_point(&near_ndc_point);
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let far_view_point = projection.unproject_point(&far_ndc_point);
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// Compute the view-space line parameters.
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let line_location = near_view_point;
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let line_direction = Unit::new_normalize(far_view_point - near_view_point);
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}
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