bendns' repos / fimg
fast image operations
make drawing functions safe
Browse Source
bendn 2023-09-22
parent f74d3dc · commit 1b5b06c
Diffstat
-rw-r--r--Cargo.toml2
-rw-r--r--src/drawing/box.rs54
-rw-r--r--src/drawing/tri.rs17
3 files changed, 28 insertions, 45 deletions
diff --git a/Cargo.toml b/Cargo.toml
index 245304f..c2a25cb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
[package]
name = "fimg"
-version = "0.4.2"
+version = "0.4.3"
authors = ["bend-n <[email protected]>"]
license = "MIT"
edition = "2021"
diff --git a/src/drawing/box.rs b/src/drawing/box.rs
index 15f183f..dd46efc 100644
--- a/src/drawing/box.rs
+++ b/src/drawing/box.rs
@@ -1,65 +1,51 @@
//! `Box<cat>`
+use std::ops::Range;
+
use crate::Image;
impl<const CHANNELS: usize> Image<&mut [u8], CHANNELS> {
/// Draw a bordered box
- ///
- /// # Safety
- ///
- /// UB if the box is out of bounds
/// ```
/// # use fimg::Image;
/// let mut b = Image::alloc(10, 9);
- /// unsafe { b.as_mut().r#box((1, 1), 7, 6, [255]) };
+ /// b.as_mut().r#box((1, 1), 7, 6, [255]);
/// # assert_eq!(b.buffer(), b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\xff\x00\x00\x00\x00\x00\x00\xff\x00\x00\xff\x00\x00\x00\x00\x00\x00\xff\x00\x00\xff\x00\x00\x00\x00\x00\x00\xff\x00\x00\xff\x00\x00\x00\x00\x00\x00\xff\x00\x00\xff\x00\x00\x00\x00\x00\x00\xff\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00")
/// ```
- pub unsafe fn r#box(
- &mut self,
- (x1, y1): (u32, u32),
- width: u32,
- height: u32,
- c: [u8; CHANNELS],
- ) {
+ pub fn r#box(&mut self, (x1, y1): (u32, u32), width: u32, height: u32, c: [u8; CHANNELS]) {
// skip sides, leave that to second loop
- for x in x1 + 1..width + x1 {
+ for x in clamp(x1 + 1..width + x1, 0..self.width()) {
// top line
- // SAFETY: responsibility is on caller
+ // SAFETY: clamped to bounds
unsafe { self.set_pixel(x, x1, c) };
- // bottom line
- // SAFETY: shift responsibility
+ // SAFETY: clamped to bounds
unsafe { self.set_pixel(x, x1 + height, c) };
}
- for y in y1..=height + y1 {
- // SAFETY: >> responsibility
+ for y in clamp(y1..height + y1 + 1, 0..self.height()) {
+ // SAFETY: clamped to bounds
unsafe { self.set_pixel(y1, y, c) };
- // SAFETY: << responsibility
+ // SAFETY: clamped to bounds
unsafe { self.set_pixel(y1 + width, y, c) };
}
}
/// Draw a *filled* box.
- ///
- /// # Safety
- ///
- /// UB if box is out of bounds
/// ```
/// # use fimg::Image;
/// let mut b = Image::alloc(10, 9);
- /// unsafe { b.as_mut().filled_box((1, 1), 7, 6, [255]) };
+ /// b.as_mut().filled_box((1, 1), 7, 6, [255]);
/// # assert_eq!(b.buffer(), b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00")
/// ```
- pub unsafe fn filled_box(
- &mut self,
- (x1, y1): (u32, u32),
- width: u32,
- height: u32,
- c: [u8; CHANNELS],
- ) {
- for x in x1..=width + x1 {
- for y in y1..=height + y1 {
- // SAFETY: fill it
+ pub fn filled_box(&mut self, (x1, y1): (u32, u32), width: u32, height: u32, c: [u8; CHANNELS]) {
+ for x in clamp(x1..1 + width + x1, 0..self.width()) {
+ for y in clamp(y1..1 + height + y1, 0..self.height()) {
+ // SAFETY: clamped to bounds
unsafe { self.set_pixel(x, y, c) };
}
}
}
}
+
+/// clamp a range with another range
+fn clamp(r: Range<u32>, within: Range<u32>) -> Range<u32> {
+ r.start.clamp(within.start, within.end)..r.end.clamp(within.start, within.end)
+}
diff --git a/src/drawing/tri.rs b/src/drawing/tri.rs
index 3cc390b..c7256c5 100644
--- a/src/drawing/tri.rs
+++ b/src/drawing/tri.rs
@@ -3,19 +3,15 @@ use crate::Image;
impl<const CHANNELS: usize> Image<&mut [u8], CHANNELS> {
/// Draw a (filled) triangle
- ///
- /// # Safety
- ///
- /// UB if any point is out of bounds
/// ```
/// # use fimg::*;
/// let mut a = Image::alloc(10, 10);
/// // draw a triangle from point a v point b v point c v
/// // with color white
- /// unsafe { a.as_mut().tri((3.0, 2.0), (8.0, 7.0), (1.0, 8.0), [255]) };
+ /// a.as_mut().tri((3.0, 2.0), (8.0, 7.0), (1.0, 8.0), [255]);
/// # assert_eq!(a.buffer(), b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff\x00\x00\x00\x00\x00\xff\xff\xff\xff\xff\xff\x00\x00\x00\x00\xff\xff\xff\xff\xff\xff\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00");
/// ```
- pub unsafe fn tri(
+ pub fn tri(
&mut self,
(x1, y1): (f32, f32),
(x2, y2): (f32, f32),
@@ -33,10 +29,11 @@ impl<const CHANNELS: usize> Image<&mut [u8], CHANNELS> {
}
let d = (x3 - x2) * (y as f32 - y2) - (y3 - y2) * (x as f32 - x2);
- if d == 0.0 || (d < 0.0) == (s + t <= 0.0) {
- // SAFETY:
- // caller gurantees triangle is in bounds, this loops over the
- // bounding box of the triangle, therefore this is fine.
+ if (d == 0.0 || (d < 0.0) == (s + t <= 0.0))
+ && x < self.width()
+ && y < self.height()
+ {
+ // SAFETY: we just checked the bounds
unsafe { self.set_pixel(x, y, c) };
}
}