Method pdf

tools/bloom-reference/src/main.rs:1655–1665

PDF (per solid angle) of the env distribution for a given direction. Evaluates the pixel the direction maps to and converts back to solid-angle measure.

(&self, direction: Vec3)

    /// direction. Evaluates the pixel the direction maps to and
    /// converts back to solid-angle measure.
    fn pdf(&self, direction: Vec3) -> f32 {
        let (x, y, sin_theta) = self.direction_to_pixel(direction);
        if sin_theta <= 0.0 {
            return 0.0;
        }
        let pixel_p = self.distribution.pixel_pdf(x, y);
        let omega_per_pixel = (2.0 * std::f32::consts::PI / self.width as f32)
            * (std::f32::consts::PI / self.height as f32)
            * sin_theta;
        pixel_p / omega_per_pixel
    }
}

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