1 files changed, 117 insertions, 0 deletions
diff --git a/stockton-levels/src/q3/brushes.rs b/stockton-levels/src/q3/brushes.rs
new file mode 100644
index 0000000..48462a2
--- /dev/null
+++ b/stockton-levels/src/q3/brushes.rs
@@ -0,0 +1,117 @@
+// Copyright (C) 2019 Oscar Shrimpton
+//
+// This file is part of stockton-bsp.
+//
+// stockton-bsp is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// stockton-bsp is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with stockton-bsp.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Parses the brushes & brushsides lumps from a bsp file
+
+/// The size of one brush record.
+const BRUSH_SIZE: usize = 4 * 3;
+
+/// The size of one brushsize record
+const SIDE_SIZE: usize = 4 * 2;
+
+use crate::helpers::slice_to_i32;
+use crate::types::{ParseError, Result};
+use crate::traits::brushes::*;
+use super::Q3BSPFile;
+
+/// Parse the brushes & brushsides lump from a bsp file.
+pub fn from_data(
+    brushes_data: &[u8],
+    sides_data: &[u8],
+    n_textures: u32,
+    n_planes: u32
+) -> Result<Box<[Brush]>> {
+    if brushes_data.len() % BRUSH_SIZE != 0 || sides_data.len() % SIDE_SIZE != 0 {
+        return Err(ParseError::Invalid);
+    }
+    let length = brushes_data.len() / BRUSH_SIZE;
+
+    let mut brushes = Vec::with_capacity(length as usize);
+    for n in 0..length {
+        let offset = n * BRUSH_SIZE;
+        let brush = &brushes_data[offset..offset + BRUSH_SIZE];
+
+        let texture_idx = slice_to_i32(&brush[8..12]) as usize;
+        if texture_idx >= n_textures as usize {
+            return Err(ParseError::Invalid);
+        }
+
+        brushes.push(Brush {
+            sides: get_sides(
+                sides_data,
+                slice_to_i32(&brush[0..4]),
+                slice_to_i32(&brush[4..8]),
+                n_textures as usize,
+                n_planes as usize
+            )?,
+            texture_idx
+        });
+    }
+
+    Ok(brushes.into_boxed_slice())
+}
+
+/// Internal function to get the relevant brushsides for a brush from the data in the brush lump.
+fn get_sides(
+    sides_data: &[u8],
+    start: i32,
+    length: i32,
+    n_textures: usize,
+    n_planes: usize,
+) -> Result<Box<[BrushSide]>> {
+    let mut sides = Vec::with_capacity(length as usize);
+
+    if length > 0 {
+        for n in start..start + length {
+            let offset = n as usize * SIDE_SIZE;
+            let brush = &sides_data[offset..offset + SIDE_SIZE];
+
+            let plane_idx = slice_to_i32(&brush[0..4]) as usize;
+            if plane_idx / 2 >= n_planes {
+                return Err(ParseError::Invalid);
+            }
+
+            let is_opposing = plane_idx % 2 != 0;
+
+            let texture_idx = slice_to_i32(&brush[4..8]) as usize;
+            if texture_idx >= n_textures {
+                return Err(ParseError::Invalid);
+            }
+
+            sides.push(BrushSide {
+                plane_idx,
+                texture_idx,
+                is_opposing
+            });
+        }
+    }
+
+    Ok(sides.into_boxed_slice())
+}
+
+
+impl<'a> HasBrushes<'a> for Q3BSPFile {
+    type BrushesIter = std::slice::Iter<'a, Brush>;
+
+    fn brushes_iter(&'a self) -> Self::BrushesIter {
+        self.brushes.iter()
+    }
+
+    fn get_brush(&'a self, index: u32) -> &'a Brush {
+        &self.brushes[index as usize]
+    }
+}