diff --git a/librashader-presets/Cargo.toml b/librashader-presets/Cargo.toml
index e426ce3..05a2de3 100644
--- a/librashader-presets/Cargo.toml
+++ b/librashader-presets/Cargo.toml
@@ -9,5 +9,8 @@ edition = "2021"
 thiserror = "1.0.37"
 nom = "7.1.1"
 nom_locate = "4.0.0"
-"librashader-common" = { path = "../librashader-common" }
-num-traits = "0.2"
\ No newline at end of file
+librashader-common = { path = "../librashader-common" }
+num-traits = "0.2"
+
+[features]
+parse_legacy_glsl = []
\ No newline at end of file
diff --git a/librashader-presets/src/parse/preset.rs b/librashader-presets/src/parse/preset.rs
index da31823..a632927 100644
--- a/librashader-presets/src/parse/preset.rs
+++ b/librashader-presets/src/parse/preset.rs
@@ -48,6 +48,7 @@ pub fn resolve_values(mut values: Vec<Value>) -> ShaderPreset {
         })
         .unwrap_or(0);
 
+    #[cfg(feature = "parse_legacy_glsl")]
     let feedback_pass = remove_if(&mut values, |v| matches!(*v, Value::FeedbackPass(_)))
         .map(|value| {
             if let Value::FeedbackPass(pass) = value {
@@ -179,8 +180,9 @@ pub fn resolve_values(mut values: Vec<Value>) -> ShaderPreset {
     }
 
     ShaderPreset {
-        shader_count,
+        #[cfg(feature = "parse_legacy_glsl")]
         feedback_pass,
+        shader_count,
         shaders,
         textures,
         parameters,
diff --git a/librashader-presets/src/preset.rs b/librashader-presets/src/preset.rs
index 61f35a7..b3d2261 100644
--- a/librashader-presets/src/preset.rs
+++ b/librashader-presets/src/preset.rs
@@ -113,10 +113,20 @@ pub struct ParameterConfig {
 
 #[derive(Debug, Clone)]
 pub struct ShaderPreset {
-    pub shader_count: i32,
+    /// Used in legacy GLSL shader semantics. If < 0, no feedback pass is used.
+    /// Otherwise, the FBO after pass #N is passed a texture to next frame
+    #[cfg(feature = "parse_legacy_glsl")]
     pub feedback_pass: i32,
+
+    /// The number of shaders enabled in the filter chain.
+    pub shader_count: i32,
     // Everything is in Vecs because the expect number of values is well below 64.
+    /// Preset information for each shader.
     pub shaders: Vec<ShaderPassConfig>,
+
+    /// Preset information for each texture.
     pub textures: Vec<TextureConfig>,
+
+    /// Preset information for each user parameter.
     pub parameters: Vec<ParameterConfig>,
 }
diff --git a/librashader-runtime-gl/src/filter_chain.rs b/librashader-runtime-gl/src/filter_chain.rs
index 2bc56fe..1fec799 100644
--- a/librashader-runtime-gl/src/filter_chain.rs
+++ b/librashader-runtime-gl/src/filter_chain.rs
@@ -37,7 +37,7 @@ pub struct FilterChain {
 
 pub struct FilterCommon {
     // semantics: ReflectSemantics,
-    pub(crate) preset: ShaderPreset,
+    pub(crate) config: FilterMutable,
     pub(crate) luts: FxHashMap<usize, Texture>,
     pub(crate) samplers: SamplerSet,
     pub output_textures: Box<[Texture]>,
@@ -46,6 +46,11 @@ pub struct FilterCommon {
     pub(crate) draw_quad: DrawQuad,
 }
 
+pub struct FilterMutable {
+    pub(crate) passes_enabled: usize,
+    pub(crate) parameters: FxHashMap<String, f32>
+}
+
 impl FilterChain {
     fn load_pass_semantics(
         uniform_semantics: &mut FxHashMap<String, UniformSemantic>,
@@ -124,8 +129,8 @@ impl FilterChain {
     }
 }
 
-type ShaderPassMeta<'a> = (
-    &'a ShaderPassConfig,
+type ShaderPassMeta = (
+    ShaderPassConfig,
     ShaderSource,
     CompilerBackend<
         impl CompileShader<GLSL, Options = GlVersion, Context = GlslangGlslContext> + ReflectShader,
@@ -135,7 +140,7 @@ type ShaderPassMeta<'a> = (
 impl FilterChain {
     /// Load a filter chain from a pre-parsed `ShaderPreset`.
     pub fn load_from_preset(preset: ShaderPreset, options: Option<&FilterChainOptions>) -> Result<FilterChain> {
-        let (passes, semantics) = FilterChain::load_preset(&preset)?;
+        let (passes, semantics) = FilterChain::load_preset(preset.shaders, &preset.textures)?;
 
         let version = options.map(|o| gl_u16_to_version(o.gl_version))
             .unwrap_or_else(|| gl_get_version());
@@ -184,9 +189,11 @@ impl FilterChain {
             history_framebuffers,
             filter_vao,
             common: FilterCommon {
-                // we don't need the reflect semantics once all locations have been bound per pass.
-                // semantics,
-                preset,
+                config: FilterMutable {
+                    passes_enabled: preset.shader_count as usize,
+                    parameters: preset.parameters.into_iter()
+                        .map(|param| (param.name, param.value)).collect(),
+                },
                 luts,
                 samplers,
                 output_textures: output_textures.into_boxed_slice(),
@@ -205,15 +212,15 @@ impl FilterChain {
     }
 
     fn load_preset(
-        preset: &ShaderPreset,
+        passes: Vec<ShaderPassConfig>,
+        textures: &[TextureConfig]
     ) -> Result<(Vec<ShaderPassMeta>, ReflectSemantics)> {
         let mut uniform_semantics: FxHashMap<String, UniformSemantic> = Default::default();
         let mut texture_semantics: FxHashMap<String, SemanticMap<TextureSemantics>> =
             Default::default();
 
-        let passes = preset
-            .shaders
-            .iter()
+        let passes = passes
+            .into_iter()
             .map(|shader| {
                 eprintln!("[gl] loading {}", &shader.name.display());
                 let source: ShaderSource = ShaderSource::load(&shader.name)?;
@@ -233,18 +240,18 @@ impl FilterChain {
                 Ok::<_, FilterChainError>((shader, source, reflect))
             })
             .into_iter()
-            .collect::<Result<Vec<(&ShaderPassConfig, ShaderSource, CompilerBackend<_>)>>>()?;
+            .collect::<Result<Vec<(ShaderPassConfig, ShaderSource, CompilerBackend<_>)>>>()?;
 
         for details in &passes {
             FilterChain::load_pass_semantics(
                 &mut uniform_semantics,
                 &mut texture_semantics,
-                details.0,
+                &details.0,
             )
         }
 
         // add lut params
-        for (index, texture) in preset.textures.iter().enumerate() {
+        for (index, texture) in textures.iter().enumerate() {
             texture_semantics.insert(
                 texture.name.clone(),
                 SemanticMap {
@@ -495,7 +502,7 @@ impl FilterChain {
                 push_buffer,
                 uniform_bindings,
                 source,
-                config: config.clone(),
+                config
             });
         }
 
@@ -572,6 +579,8 @@ impl FilterChain {
     ///
     /// When this frame returns, GL_FRAMEBUFFER is bound to 0.
     pub fn frame(&mut self, count: usize, viewport: &Viewport, input: &GlImage, options: Option<&FrameOptions>) -> Result<()> {
+        // limit number of passes to those enabled.
+        let passes = &mut self.passes[0..self.common.config.passes_enabled];
         if let Some(options) = options {
             if options.clear_history {
                 for framebuffer in &self.history_framebuffers {
@@ -580,7 +589,7 @@ impl FilterChain {
             }
         }
 
-        if self.passes.is_empty() {
+        if passes.is_empty() {
             return Ok(());
         }
 
@@ -590,8 +599,8 @@ impl FilterChain {
             gl::BindVertexArray(self.filter_vao);
         }
 
-        let filter = self.passes[0].config.filter;
-        let wrap_mode = self.passes[0].config.wrap_mode;
+        let filter = passes[0].config.filter;
+        let wrap_mode = passes[0].config.wrap_mode;
 
         // update history
         for (texture, fbo) in self
@@ -608,7 +617,7 @@ impl FilterChain {
             .feedback_textures
             .iter_mut()
             .zip(self.feedback_framebuffers.iter())
-            .zip(self.passes.iter())
+            .zip(passes.iter())
         {
             texture.image = fbo
                 .as_texture(pass.config.filter, pass.config.wrap_mode)
@@ -626,7 +635,7 @@ impl FilterChain {
         let mut source = original;
 
         // rescale render buffers to ensure all bindings are valid.
-        for (index, pass) in self.passes.iter_mut().enumerate() {
+        for (index, pass) in passes.iter_mut().enumerate() {
             self.output_framebuffers[index].scale(
                 pass.config.scaling.clone(),
                 pass.get_format(),
@@ -644,8 +653,8 @@ impl FilterChain {
             )?;
         }
 
-        let passes_len = self.passes.len();
-        let (pass, last) = self.passes.split_at_mut(passes_len - 1);
+        let passes_len = passes.len();
+        let (pass, last) = passes.split_at_mut(passes_len - 1);
 
         for (index, pass) in pass.iter_mut().enumerate() {
             let target = &self.output_framebuffers[index];
diff --git a/librashader-runtime-gl/src/filter_pass.rs b/librashader-runtime-gl/src/filter_pass.rs
index d67043c..40dd89f 100644
--- a/librashader-runtime-gl/src/filter_pass.rs
+++ b/librashader-runtime-gl/src/filter_pass.rs
@@ -506,13 +506,11 @@ impl FilterPass {
                 .map(|f| f.initial)
                 .unwrap_or(0f32);
 
-            let value = parent
-                .preset
+            let value = *parent
+                .config
                 .parameters
-                .iter()
-                .find(|&p| p.name == id)
-                .map(|p| p.value)
-                .unwrap_or(default);
+                .get(id)
+                .unwrap_or(&default);
 
             FilterPass::build_float(location.location(), &mut buffer[offset..][..4], value)
         }
diff --git a/librashader-runtime-gl/src/lib.rs b/librashader-runtime-gl/src/lib.rs
index 669e0f7..fdfa43e 100644
--- a/librashader-runtime-gl/src/lib.rs
+++ b/librashader-runtime-gl/src/lib.rs
@@ -31,7 +31,7 @@ mod tests {
     fn triangle_gl() {
         let (glfw, window, events, shader, vao) = hello_triangle::setup();
         let mut filter =
-            FilterChain::load_from_path("../test/slang-shaders/crt/crt-royale.slangp", None)
+            FilterChain::load_from_path("../test/slang-shaders/vhs/VHSPro.slangp", None)
                 .unwrap();
         hello_triangle::do_loop(glfw, window, events, shader, vao, &mut filter);
     }
diff --git a/librashader/src/lib.rs b/librashader/src/lib.rs
index 74a6665..e155258 100644
--- a/librashader/src/lib.rs
+++ b/librashader/src/lib.rs
@@ -67,3 +67,16 @@ pub use librashader_common::{
     WrapMode
 };
 
+pub mod util {
+    use librashader_preprocess::{PreprocessError, ShaderParameter, ShaderSource};
+    use librashader_presets::ShaderPreset;
+
+    pub fn get_parameter_meta(preset: &ShaderPreset) -> Result<impl Iterator<Item = ShaderParameter>, PreprocessError> {
+        let iters: Result<Vec<Vec<ShaderParameter>>, PreprocessError> = preset.shaders.iter()
+            .map(|s| ShaderSource::load(&s.name).map(|s| s.parameters))
+            .into_iter()
+            .collect();
+        let iters = iters?;
+        Ok(iters.into_iter().flatten())
+    }
+}