From 9418cbaa2410d7e14f3c36e7b582db1024aec747 Mon Sep 17 00:00:00 2001
From: Elias Batek <desisma@heidel.beer>
Date: Sun, 6 Oct 2024 01:35:08 +0200
Subject: [PATCH] Document the coordinate system used by PixmapPaint

---
 pixmappaint.d | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/pixmappaint.d b/pixmappaint.d
index d496d7d..3aaea4f 100644
--- a/pixmappaint.d
+++ b/pixmappaint.d
@@ -14,6 +14,22 @@
 		This module is $(B work in progress).
 		API is subject to changes until further notice.
 	)
+
+	### The coordinate system
+
+	The top left corner of a pixmap is its $(B origin) `(0,0)`.
+
+	The $(horizontal axis) is called `x`.
+	Its corresponding length/dimension is known as `width`.
+
+	The letter `y` is used to describe the $(B vertical axis).
+	Its corresponding length/dimension is known as `height`.
+
+	```
+	0 → x
+	↓
+	x
+	```
  +/
 module arsd.pixmappaint;