From 95f6babd5e2ccc66bf7e97f74f804ddac4cf2fef Mon Sep 17 00:00:00 2001
From: Kae <80987908+Novaenia@users.noreply.github.com>
Date: Fri, 3 May 2024 08:53:44 +1000
Subject: [PATCH] scaling functions now warn instead of crashing with negative
 scales

---
 source/core/StarImageProcessing.cpp | 21 ++++++++++++++++-----
 source/core/StarImageProcessing.hpp |  6 +++---
 2 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/source/core/StarImageProcessing.cpp b/source/core/StarImageProcessing.cpp
index b803470..6d2c51d 100644
--- a/source/core/StarImageProcessing.cpp
+++ b/source/core/StarImageProcessing.cpp
@@ -6,12 +6,15 @@
 #include "StarImage.hpp"
 #include "StarStringView.hpp"
 #include "StarEncode.hpp"
-//#include "StarTime.hpp"
-//#include "StarLogging.hpp"
+#include "StarLogging.hpp"
 
 namespace Star {
 
-Image scaleNearest(Image const& srcImage, Vec2F const& scale) {
+Image scaleNearest(Image const& srcImage, Vec2F scale) {
+  if (scale[0] < 0.0f || scale[1] < 0.0f) {
+    Logger::warn("Negative scale in scaleNearest({})", scale);
+    scale = scale.piecewiseMax(Vec2F::filled(0.f));
+  }
   Vec2U srcSize = srcImage.size();
   Vec2U destSize = Vec2U::round(vmult(Vec2F(srcSize), scale));
   destSize[0] = max(destSize[0], 1u);
@@ -26,7 +29,11 @@ Image scaleNearest(Image const& srcImage, Vec2F const& scale) {
   return destImage;
 }
 
-Image scaleBilinear(Image const& srcImage, Vec2F const& scale) {
+Image scaleBilinear(Image const& srcImage, Vec2F scale) {
+  if (scale[0] < 0.0f || scale[1] < 0.0f) {
+    Logger::warn("Negative scale in scaleBilinear({})", scale);
+    scale = scale.piecewiseMax(Vec2F::filled(0.f));
+  }
   Vec2U srcSize = srcImage.size();
   Vec2U destSize = Vec2U::round(vmult(Vec2F(srcSize), scale));
   destSize[0] = max(destSize[0], 1u);
@@ -50,7 +57,11 @@ Image scaleBilinear(Image const& srcImage, Vec2F const& scale) {
   return destImage;
 }
 
-Image scaleBicubic(Image const& srcImage, Vec2F const& scale) {
+Image scaleBicubic(Image const& srcImage, Vec2F scale) {
+  if (scale[0] < 0.0f || scale[1] < 0.0f) {
+    Logger::warn("Negative scale in scaleBicubic({})", scale);
+    scale = scale.piecewiseMax(Vec2F::filled(0.f));
+  }
   Vec2U srcSize = srcImage.size();
   Vec2U destSize = Vec2U::round(vmult(Vec2F(srcSize), scale));
   destSize[0] = max(destSize[0], 1u);
diff --git a/source/core/StarImageProcessing.hpp b/source/core/StarImageProcessing.hpp
index 8316d18..4022d38 100644
--- a/source/core/StarImageProcessing.hpp
+++ b/source/core/StarImageProcessing.hpp
@@ -10,9 +10,9 @@ STAR_CLASS(Image);
 
 STAR_EXCEPTION(ImageOperationException, StarException);
 
-Image scaleNearest(Image const& srcImage, Vec2F const& scale);
-Image scaleBilinear(Image const& srcImage, Vec2F const& scale);
-Image scaleBicubic(Image const& srcImage, Vec2F const& scale);
+Image scaleNearest(Image const& srcImage, Vec2F scale);
+Image scaleBilinear(Image const& srcImage, Vec2F scale);
+Image scaleBicubic(Image const& srcImage, Vec2F scale);
 
 StringList colorDirectivesFromConfig(JsonArray const& directives);
 String paletteSwapDirectivesFromConfig(Json const& swaps);