1 files changed, 85 insertions, 5 deletions

diff --git a/engine/src/object.rs b/engine/src/object.rs
index a8cd076..4112bcb 100644
--- a/engine/src/object.rs
+++ b/engine/src/object.rs
@@ -1,3 +1,7 @@
+use std::fs::read_to_string;
+use std::io::Error as IoError;
+use std::path::{Path, PathBuf};
+
 use crate::opengl::shader::{
     Error as ShaderError,
     Kind as ShaderKind,
@@ -5,13 +9,17 @@ use crate::opengl::shader::{
     Shader,
 };
 use crate::renderer::Renderable;
+use crate::shader_preprocessor::{Error as ShaderPreprocessorError, ShaderPreprocessor};
 use crate::texture::Texture;
 use crate::transform::Transform;
 use crate::vector::Vec3;
 use crate::vertex::Vertex;
 
-const FRAG_SHADER_COLOR: &str = include_str!("../fragment-color.glsl");
-const FRAG_SHADER_TEXTURE: &str = include_str!("../fragment-texture.glsl");
+const SHADER_DIR: &str = "engine";
+
+const VERTEX_SHADER_FILE: &str = "vertex.glsl";
+const FRAG_SHADER_COLOR_FILE: &str = "fragment-color.glsl";
+const FRAG_SHADER_TEXTURE_FILE: &str = "fragment-texture.glsl";
 
 #[derive(Debug)]
 pub struct Object
@@ -114,16 +122,72 @@ impl Builder
     /// - Linking the shader program fails
     pub fn build(self, id: Id) -> Result<Object, Error>
     {
+        let vertex_shader_file = Path::new(SHADER_DIR).join(VERTEX_SHADER_FILE);
+
+        let fragment_shader_color_file =
+            Path::new(SHADER_DIR).join(FRAG_SHADER_COLOR_FILE);
+
+        let fragment_shader_texture_file =
+            Path::new(SHADER_DIR).join(FRAG_SHADER_TEXTURE_FILE);
+
+        let vertex_shader_content =
+            read_to_string(&vertex_shader_file).map_err(|err| {
+                Error::ReadShaderFailed {
+                    source: err,
+                    shader_file: vertex_shader_file.clone(),
+                }
+            })?;
+
+        let fragment_shader_color_content = read_to_string(&fragment_shader_color_file)
+            .map_err(|err| Error::ReadShaderFailed {
+            source: err,
+            shader_file: fragment_shader_color_file.clone(),
+        })?;
+
+        let fragment_shader_texture_content =
+            read_to_string(&fragment_shader_texture_file).map_err(|err| {
+                Error::ReadShaderFailed {
+                    source: err,
+                    shader_file: fragment_shader_texture_file.clone(),
+                }
+            })?;
+
+        let shader_preprocessor = ShaderPreprocessor::new(PathBuf::from(SHADER_DIR));
+
+        let vertex_shader_content_preprocessed = shader_preprocessor
+            .preprocess(vertex_shader_content, &vertex_shader_file)
+            .map_err(|err| Error::PreprocessShaderFailed {
+                source: err,
+                shader_file: vertex_shader_file,
+            })?;
+
+        let frag_shader_color_content_preprocessed = shader_preprocessor
+            .preprocess(fragment_shader_color_content, &fragment_shader_color_file)
+            .map_err(|err| Error::PreprocessShaderFailed {
+                source: err,
+                shader_file: fragment_shader_color_file,
+            })?;
+
+        let frag_shader_texture_content_preprocessed = shader_preprocessor
+            .preprocess(
+                fragment_shader_texture_content,
+                &fragment_shader_texture_file,
+            )
+            .map_err(|err| Error::PreprocessShaderFailed {
+                source: err,
+                shader_file: fragment_shader_texture_file,
+            })?;
+
         let vertex_shader =
-            Self::create_shader(ShaderKind::Vertex, include_str!("../vertex.glsl"))
+            Self::create_shader(ShaderKind::Vertex, &vertex_shader_content_preprocessed)
                 .map_err(Error::CreateVertexShaderFailed)?;
 
         let fragment_shader = Self::create_shader(
             ShaderKind::Fragment,
             if self.texture.is_some() {
-                FRAG_SHADER_TEXTURE
+                &frag_shader_texture_content_preprocessed
             } else {
-                FRAG_SHADER_COLOR
+                &frag_shader_color_content_preprocessed
             },
         )
         .map_err(Error::CreateFragmentShaderFailed)?;
@@ -173,6 +237,22 @@ pub enum Error
 
     #[error("Failed to link shader program")]
     LinkShaderProgramFailed(#[source] ShaderError),
+
+    #[error("Failed to read shader {}", shader_file.display())]
+    ReadShaderFailed
+    {
+        #[source]
+        source: IoError,
+        shader_file: PathBuf,
+    },
+
+    #[error("Failed to preprocess shader {}", shader_file.display())]
+    PreprocessShaderFailed
+    {
+        #[source]
+        source: ShaderPreprocessorError,
+        shader_file: PathBuf,
+    },
 }
 
 /// Object ID.