rescale intensities to the "real" values from scale 0 to 1

(cherry picked from commit fd90816)

Author: dancergraham

src/lib.rs

@@ -52,6 +52,8 @@ unsafe fn read_points(py: Python<'_>, filepath: &str) -> PyResult<E57> {
     let mut color_vec = Vec::with_capacity(pc.records as usize * 3);
     let mut intensity_vec = Vec::with_capacity(pc.records as usize);
     let mut nrows = 0;
+    let intensity_min = pc.intensity_limits.map(|limits| limits.min).unwrap_or(0.0);
+    let intensity_max = pc.intensity_limits.map(|limits| limits.max).unwrap_or(1.0);
     for pointcloud in file.pointclouds() {
         let mut iter = file
             .pointcloud_simple(&pointcloud)
@@ -67,14 +69,12 @@ unsafe fn read_points(py: Python<'_>, filepath: &str) -> PyResult<E57> {
                 point_vec.extend([x, y, z]);
                 nrows += 1
             }
-            // if let Some(intensity) = p.intensity{
-            //     vec.append(intensity as f64)
-            // }
             if let Some(color) = p.color {
                 color_vec.extend([color.red, color.green, color.blue])
             }
             if let Some(intensity) = p.intensity {
-                intensity_vec.push(intensity)
+                let rescaled_intensity = (intensity * (intensity_max - intensity_min)) + intensity_min;
+                intensity_vec.push(rescaled_intensity)
             }
         }
     }