From 7f6f97128492092b82af6298e1c3d863dea07518 Mon Sep 17 00:00:00 2001
From: Ed Yu <edyu@users.noreply.github.com>
Date: Mon, 8 Jan 2024 15:08:09 -0800
Subject: [PATCH] Fix math/fixed floor/ceil/round

---
 core/math/fixed/fixed.odin | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/core/math/fixed/fixed.odin b/core/math/fixed/fixed.odin
index 5d63bf7be..d347e9c11 100644
--- a/core/math/fixed/fixed.odin
+++ b/core/math/fixed/fixed.odin
@@ -88,17 +88,19 @@ div_sat :: proc(x, y: $T/Fixed($Backing, $Fraction_Width)) -> (z: T) {
 
 @(require_results)
 floor :: proc(x: $T/Fixed($Backing, $Fraction_Width)) -> Backing {
-	return x.i >> Fraction_Width
+	if x.i >= 0 {
+		return x.i >> Fraction_Width
+	} else {
+		return (x.i - (1 << (Fraction_Width - 1)) + (1 << (Fraction_Width - 2))) >> Fraction_Width
+	}
 }
 @(require_results)
 ceil :: proc(x: $T/Fixed($Backing, $Fraction_Width)) -> Backing {
-	Integer :: 8*size_of(Backing) - Fraction_Width
-	return (x.i + (1 << Integer-1)) >> Fraction_Width
+	return (x.i + (1 << Fraction_Width - 1)) >> Fraction_Width
 }
 @(require_results)
 round :: proc(x: $T/Fixed($Backing, $Fraction_Width)) -> Backing {
-	Integer :: 8*size_of(Backing) - Fraction_Width
-	return (x.i + (1 << (Integer - 1))) >> Fraction_Width
+	return (x.i + (1 << (Fraction_Width - 1))) >> Fraction_Width
 }