textium: texture utils

textium/src/texture.rs

@@ -0,0 +1,42 @@
+use std::borrow::Cow;
+
+use glium::texture::{RawImage2d, Texture2dDataSource};
+pub use glium::texture::PixelValue;
+
+
+pub struct Texture2dData<T> where T: Clone {
+    pub data: Vec<T>,
+    pub width: u32,
+    pub height: u32,
+}
+
+impl<'a, P> Texture2dDataSource<'a> for &'a Texture2dData<P>
+    where P: Clone + PixelValue
+{
+    type Data = P;
+
+    fn into_raw(self) -> RawImage2d<'a, P> {
+        RawImage2d {
+            data: Cow::Borrowed(&self.data),
+            width: self.width,
+            height: self.height,
+            format: <P as PixelValue>::get_format(),
+        }
+    }
+}
+
+pub fn get_nearest_pow2(mut x: u32) -> u32 {
+    // A nice, fast bit hack.
+    // Taken from https://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
+
+    assert!(x > 0);
+
+    x -= 1;
+    x = x | (x >> 1);
+    x = x | (x >> 2);
+    x = x | (x >> 4);
+    x = x | (x >> 8);
+    x = x | (x >> 16);
+
+    x + 1
+}