myth_resources/
fxaa.rs

1//! FXAA (Fast Approximate Anti-Aliasing) Configuration
2//!
3//! This module defines FXAA settings as a pure data structure, following the same
4//! pattern as [`BloomSettings`](super::bloom::BloomSettings) and
5//! [`ToneMappingSettings`](super::tone_mapping::ToneMappingSettings).
6//!
7//! FXAA is a screen-space anti-aliasing technique that identifies aliased edges
8//! via luma contrast detection and applies sub-pixel smoothing. It operates on
9//! LDR (post-tone-mapped) images and is therefore placed **after** tone mapping
10//! in the HDR pipeline.
11//!
12//! # Quality Presets
13//!
14//! | Preset   | Iterations | Best for              |
15//! |----------|------------|----------------------|
16//! | `Low`    | 4          | Mobile / low-end GPU |
17//! | `Medium` | 8          | Default balance      |
18//! | `High`   | 12         | Maximum quality      |
19//!
20//! # Usage
21//!
22//! ```rust,ignore
23//! // Access via scene
24//! scene.fxaa.enabled = true;
25//! scene.fxaa.set_quality(FxaaQuality::High);
26//! ```
27
28/// FXAA quality preset.
29///
30/// Controls the number of edge exploration iterations in the FXAA shader.
31/// Higher quality means more iterations and better edge detection at the
32/// cost of additional texture samples per pixel.
33#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Default)]
34pub enum FxaaQuality {
35    /// 4 iterations — suitable for mobile and low-end GPUs.
36    Low,
37    /// 8 iterations — good balance of quality and performance (default).
38    Medium,
39    /// 12 iterations — maximum edge exploration quality.
40    #[default]
41    High,
42}
43
44impl FxaaQuality {
45    /// Returns a human-readable name for the quality preset.
46    #[must_use]
47    pub const fn name(self) -> &'static str {
48        match self {
49            Self::Low => "Low",
50            Self::Medium => "Medium",
51            Self::High => "High",
52        }
53    }
54
55    /// Returns all available quality presets.
56    #[must_use]
57    pub const fn all() -> &'static [FxaaQuality] {
58        &[Self::Low, Self::Medium, Self::High]
59    }
60
61    /// Returns the shader define key for this quality preset.
62    ///
63    /// Used by `FxaaPass` to select the correct shader variant.
64    #[must_use]
65    pub const fn define_key(self) -> &'static str {
66        match self {
67            Self::Low => "FXAA_QUALITY_LOW",
68            Self::Medium => "FXAA_QUALITY_MEDIUM",
69            Self::High => "FXAA_QUALITY_HIGH",
70        }
71    }
72}
73
74/// FXAA post-processing configuration.
75///
76/// This is a lightweight settings struct — FXAA has no per-frame GPU uniforms,
77/// only a quality preset that affects shader compilation.
78///
79/// # Usage
80///
81/// ```rust,ignore
82/// let fxaa = &mut scene.fxaa;
83/// fxaa.set_quality(FxaaQuality::High);
84/// ```
85#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Default)]
86pub struct FxaaSettings {
87    /// Quality preset controlling edge exploration iterations.
88    pub quality: FxaaQuality,
89}
90
91impl FxaaSettings {
92    /// Creates new FXAA settings with default values (enabled, medium quality).
93    #[must_use]
94    pub fn new() -> Self {
95        Self::default()
96    }
97
98    /// Returns the current quality preset.
99    #[inline]
100    #[must_use]
101    pub fn quality(&self) -> FxaaQuality {
102        self.quality
103    }
104
105    #[inline]
106    pub fn set_quality(&mut self, quality: FxaaQuality) {
107        self.quality = quality;
108    }
109}
myth_resources/fxaa.rs

myth_resources/
fxaa.rs
