StratoSDK is a framework with a declarative approach similar to Flutter/React, written and designed entirely for Rust.
| 1 | //! Validated rectangle type with GPU-safe coordinate guarantees. |
| 2 | //! |
| 3 | //! # Safety Guarantees |
| 4 | //! |
| 5 | //! `ValidatedRect` provides the following invariants: |
| 6 | //! - All coordinates are finite (no NaN, no Infinity) |
| 7 | //! - Width and height are non-negative |
| 8 | //! - All values are clamped to prevent GPU overflow |
| 9 | //! |
| 10 | //! # Example |
| 11 | //! |
| 12 | //! ```rust |
| 13 | //! use strato_core::validated_rect::ValidatedRect; |
| 14 | //! |
| 15 | //! // Valid construction |
| 16 | //! let rect = ValidatedRect::new(10.0, 20.0, 100.0, 50.0).unwrap(); |
| 17 | //! |
| 18 | //! // Invalid construction (NaN) |
| 19 | //! assert!(ValidatedRect::new(f32::NAN, 0.0, 10.0, 10.0).is_err()); |
| 20 | //! ``` |
| 21 | |
| 22 | use crate::error::TaffyValidationError; |
| 23 | |
| 24 | /// Maximum coordinate value to prevent GPU overflow. |
| 25 | /// |
| 26 | /// @note This is a conservative limit that all major GPUs can handle. |
| 27 | /// @rationale Prevents floating-point precision issues at extreme values. |
| 28 | const MAX_COORD: f32 = 1_000_000.0; |
| 29 | |
| 30 | /// Rectangle with GUARANTEED validity of all coordinates. |
| 31 | /// |
| 32 | /// # Invariants |
| 33 | /// |
| 34 | /// All instances of `ValidatedRect` satisfy: |
| 35 | /// - `x`, `y` are finite and in range `[-MAX_COORD, MAX_COORD]` |
| 36 | /// - `width`, `height` are finite, non-negative, and `<= MAX_COORD` |
| 37 | /// |
| 38 | /// These invariants are enforced at construction time and cannot be violated |
| 39 | /// through safe Rust code. |
| 40 | #[derive(Debug, Clone, Copy, PartialEq)] |
| 41 | pub struct ValidatedRect { |
| 42 | x: f32, |
| 43 | y: f32, |
| 44 | width: f32, |
| 45 | height: f32, |
| 46 | } |
| 47 | |
| 48 | impl ValidatedRect { |
| 49 | /// Create a new validated rectangle. |
| 50 | /// |
| 51 | /// # Arguments |
| 52 | /// |
| 53 | /// * `x` - X position (must be finite) |
| 54 | /// * `y` - Y position (must be finite) |
| 55 | /// * `width` - Width (must be finite and >= 0.0) |
| 56 | /// * `height` - Height (must be finite and >= 0.0) |
| 57 | /// |
| 58 | /// # Returns |
| 59 | /// |
| 60 | /// * `Ok(ValidatedRect)` - If all values are valid |
| 61 | /// * `Err(TaffyValidationError)` - If any validation fails |
| 62 | /// |
| 63 | /// # Errors |
| 64 | /// |
| 65 | /// * `TaffyValidationError::NonFiniteValue` - If any value is NaN or Infinity |
| 66 | /// * `TaffyValidationError::NegativeDimension` - If width or height < 0.0 |
| 67 | /// |
| 68 | /// # Safety |
| 69 | /// |
| 70 | /// Thread-safety: This function is thread-safe. |
| 71 | /// |
| 72 | /// # Performance |
| 73 | /// |
| 74 | /// WCET: O(1), ~10 floating-point comparisons |
| 75 | pub fn new(x: f32, y: f32, width: f32, height: f32) -> Result<Self, TaffyValidationError> { |
| 76 | // STEP 1: Check is_finite() for all 4 values |
| 77 | if !x.is_finite() || !y.is_finite() || !width.is_finite() || !height.is_finite() { |
| 78 | return Err(TaffyValidationError::NonFiniteValue); |
| 79 | } |
| 80 | |
| 81 | // STEP 2: Check width >= 0.0 && height >= 0.0 |
| 82 | if width < 0.0 || height < 0.0 { |
| 83 | return Err(TaffyValidationError::NegativeDimension { width, height }); |
| 84 | } |
| 85 | |
| 86 | // STEP 3: Clamp all values to safe range |
| 87 | let x_clamped = x.clamp(-MAX_COORD, MAX_COORD); |
| 88 | let y_clamped = y.clamp(-MAX_COORD, MAX_COORD); |
| 89 | let width_clamped = width.min(MAX_COORD); |
| 90 | let height_clamped = height.min(MAX_COORD); |
| 91 | |
| 92 | Ok(Self { |
| 93 | x: x_clamped, |
| 94 | y: y_clamped, |
| 95 | width: width_clamped, |
| 96 | height: height_clamped, |
| 97 | }) |
| 98 | } |
| 99 | |
| 100 | /// Create a validated rectangle from Taffy layout output. |
| 101 | /// |
| 102 | /// # Arguments |
| 103 | /// |
| 104 | /// * `layout` - Taffy layout result |
| 105 | /// |
| 106 | /// # Returns |
| 107 | /// |
| 108 | /// * `Ok(ValidatedRect)` - If Taffy output is valid |
| 109 | /// * `Err(TaffyValidationError)` - If Taffy produced invalid coordinates |
| 110 | /// |
| 111 | /// # Note |
| 112 | /// |
| 113 | /// Taffy COULD potentially produce invalid values in edge cases |
| 114 | /// (e.g., overflow from extreme percentages). This function catches those. |
| 115 | pub fn from_taffy(layout: &taffy::Layout) -> Result<Self, TaffyValidationError> { |
| 116 | Self::new( |
| 117 | layout.location.x, |
| 118 | layout.location.y, |
| 119 | layout.size.width, |
| 120 | layout.size.height, |
| 121 | ) |
| 122 | } |
| 123 | |
| 124 | /// Zero-size rectangle at origin. |
| 125 | /// |
| 126 | /// # Returns |
| 127 | /// |
| 128 | /// A valid rectangle with x=0, y=0, width=0, height=0. |
| 129 | #[inline] |
| 130 | pub fn zero() -> Self { |
| 131 | // SAFETY: All values are 0.0, which is finite and non-negative |
| 132 | Self { |
| 133 | x: 0.0, |
| 134 | y: 0.0, |
| 135 | width: 0.0, |
| 136 | height: 0.0, |
| 137 | } |
| 138 | } |
| 139 | |
| 140 | /// Get X position. |
| 141 | #[inline] |
| 142 | pub fn x(&self) -> f32 { |
| 143 | self.x |
| 144 | } |
| 145 | |
| 146 | /// Get Y position. |
| 147 | #[inline] |
| 148 | pub fn y(&self) -> f32 { |
| 149 | self.y |
| 150 | } |
| 151 | |
| 152 | /// Get width. |
| 153 | #[inline] |
| 154 | pub fn width(&self) -> f32 { |
| 155 | self.width |
| 156 | } |
| 157 | |
| 158 | /// Get height. |
| 159 | #[inline] |
| 160 | pub fn height(&self) -> f32 { |
| 161 | self.height |
| 162 | } |
| 163 | |
| 164 | /// Get right edge (x + width). |
| 165 | #[inline] |
| 166 | pub fn right(&self) -> f32 { |
| 167 | self.x + self.width |
| 168 | } |
| 169 | |
| 170 | /// Get bottom edge (y + height). |
| 171 | #[inline] |
| 172 | pub fn bottom(&self) -> f32 { |
| 173 | self.y + self.height |
| 174 | } |
| 175 | |
| 176 | /// Check if a point is inside this rectangle. |
| 177 | /// |
| 178 | /// # Arguments |
| 179 | /// |
| 180 | /// * `px` - Point X coordinate |
| 181 | /// * `py` - Point Y coordinate |
| 182 | /// |
| 183 | /// # Returns |
| 184 | /// |
| 185 | /// `true` if point is inside or on the boundary. |
| 186 | #[inline] |
| 187 | pub fn contains(&self, px: f32, py: f32) -> bool { |
| 188 | px >= self.x && px <= self.right() && py >= self.y && py <= self.bottom() |
| 189 | } |
| 190 | |
| 191 | /// Convert to tuple (x, y, width, height). |
| 192 | #[inline] |
| 193 | pub fn to_tuple(&self) -> (f32, f32, f32, f32) { |
| 194 | (self.x, self.y, self.width, self.height) |
| 195 | } |
| 196 | |
| 197 | /// Convert to array [x, y, width, height]. |
| 198 | #[inline] |
| 199 | pub fn to_array(&self) -> [f32; 4] { |
| 200 | [self.x, self.y, self.width, self.height] |
| 201 | } |
| 202 | } |
| 203 | |
| 204 | impl Default for ValidatedRect { |
| 205 | fn default() -> Self { |
| 206 | Self::zero() |
| 207 | } |
| 208 | } |
| 209 | |
| 210 | #[cfg(test)] |
| 211 | mod tests { |
| 212 | use super::*; |
| 213 | |
| 214 | #[test] |
| 215 | fn test_validated_rect_valid_creation() { |
| 216 | let rect = ValidatedRect::new(10.0, 20.0, 100.0, 50.0); |
| 217 | assert!(rect.is_ok()); |
| 218 | let rect = rect.unwrap(); |
| 219 | assert_eq!(rect.x(), 10.0); |
| 220 | assert_eq!(rect.y(), 20.0); |
| 221 | assert_eq!(rect.width(), 100.0); |
| 222 | assert_eq!(rect.height(), 50.0); |
| 223 | } |
| 224 | |
| 225 | #[test] |
| 226 | fn test_validated_rect_rejects_nan() { |
| 227 | assert!(ValidatedRect::new(f32::NAN, 0.0, 10.0, 10.0).is_err()); |
| 228 | assert!(ValidatedRect::new(0.0, f32::NAN, 10.0, 10.0).is_err()); |
| 229 | assert!(ValidatedRect::new(0.0, 0.0, f32::NAN, 10.0).is_err()); |
| 230 | assert!(ValidatedRect::new(0.0, 0.0, 10.0, f32::NAN).is_err()); |
| 231 | } |
| 232 | |
| 233 | #[test] |
| 234 | fn test_validated_rect_rejects_infinity() { |
| 235 | assert!(ValidatedRect::new(f32::INFINITY, 0.0, 10.0, 10.0).is_err()); |
| 236 | assert!(ValidatedRect::new(f32::NEG_INFINITY, 0.0, 10.0, 10.0).is_err()); |
| 237 | assert!(ValidatedRect::new(0.0, 0.0, f32::INFINITY, 10.0).is_err()); |
| 238 | } |
| 239 | |
| 240 | #[test] |
| 241 | fn test_validated_rect_rejects_negative_dimensions() { |
| 242 | let result = ValidatedRect::new(0.0, 0.0, -10.0, 10.0); |
| 243 | assert!(matches!( |
| 244 | result, |
| 245 | Err(TaffyValidationError::NegativeDimension { .. }) |
| 246 | )); |
| 247 | |
| 248 | let result = ValidatedRect::new(0.0, 0.0, 10.0, -5.0); |
| 249 | assert!(matches!( |
| 250 | result, |
| 251 | Err(TaffyValidationError::NegativeDimension { .. }) |
| 252 | )); |
| 253 | } |
| 254 | |
| 255 | #[test] |
| 256 | fn test_validated_rect_allows_negative_position() { |
| 257 | // Negative x/y is valid (off-screen rendering) |
| 258 | let rect = ValidatedRect::new(-50.0, -30.0, 100.0, 50.0); |
| 259 | assert!(rect.is_ok()); |
| 260 | let rect = rect.unwrap(); |
| 261 | assert_eq!(rect.x(), -50.0); |
| 262 | assert_eq!(rect.y(), -30.0); |
| 263 | } |
| 264 | |
| 265 | #[test] |
| 266 | fn test_validated_rect_clamps_extreme_values() { |
| 267 | let rect = ValidatedRect::new(2_000_000.0, -2_000_000.0, 10.0, 10.0).unwrap(); |
| 268 | assert!(rect.x() <= MAX_COORD); |
| 269 | assert!(rect.y() >= -MAX_COORD); |
| 270 | } |
| 271 | |
| 272 | #[test] |
| 273 | fn test_validated_rect_zero() { |
| 274 | let rect = ValidatedRect::zero(); |
| 275 | assert_eq!(rect.x(), 0.0); |
| 276 | assert_eq!(rect.y(), 0.0); |
| 277 | assert_eq!(rect.width(), 0.0); |
| 278 | assert_eq!(rect.height(), 0.0); |
| 279 | } |
| 280 | |
| 281 | #[test] |
| 282 | fn test_validated_rect_contains() { |
| 283 | let rect = ValidatedRect::new(10.0, 10.0, 20.0, 20.0).unwrap(); |
| 284 | |
| 285 | // Inside |
| 286 | assert!(rect.contains(15.0, 15.0)); |
| 287 | assert!(rect.contains(20.0, 20.0)); |
| 288 | |
| 289 | // On boundary |
| 290 | assert!(rect.contains(10.0, 10.0)); |
| 291 | assert!(rect.contains(30.0, 30.0)); |
| 292 | |
| 293 | // Outside |
| 294 | assert!(!rect.contains(5.0, 15.0)); |
| 295 | assert!(!rect.contains(15.0, 5.0)); |
| 296 | assert!(!rect.contains(35.0, 15.0)); |
| 297 | } |
| 298 | |
| 299 | #[test] |
| 300 | fn test_validated_rect_edges() { |
| 301 | let rect = ValidatedRect::new(10.0, 20.0, 100.0, 50.0).unwrap(); |
| 302 | assert_eq!(rect.right(), 110.0); |
| 303 | assert_eq!(rect.bottom(), 70.0); |
| 304 | } |
| 305 | } |
| 306 |