From 9c5e872f9c4f8a0a1d5d802d9d56b3a4d6862e83 Mon Sep 17 00:00:00 2001
From: Rangi <sylvie.oukaour+rangi42@gmail.com>
Date: Thu, 10 Sep 2026 16:41:32 -0400
Subject: [PATCH] First color of `-c` palettes with transparent pixels is
 transparent $8000, not unspecified $ffff

---
 src/gfx/process.cpp                   |  14 ++++++++++++--
 test/gfx/implicit-transparent.out.pal | Bin 0 -> 8 bytes
 2 files changed, 12 insertions(+), 2 deletions(-)
 create mode 100644 test/gfx/implicit-transparent.out.pal

diff --git a/src/gfx/process.cpp b/src/gfx/process.cpp
index f576894e..81f82ab1 100644
--- a/src/gfx/process.cpp
+++ b/src/gfx/process.cpp
@@ -365,8 +365,9 @@ static std::pair<std::vector<size_t>, std::vector<Palette>>
 	// LCOV_EXCL_STOP
 
 	std::vector<Palette> palettes(nbPalettes);
+
 	// If the image contains at least one transparent pixel, force transparency in the first slot of
-	// all palettes
+	// all palettes.
 	if (options.hasTransparentPixels) {
 		for (Palette &pal : palettes) {
 			pal.colors[0] = Rgba::transparent;
@@ -400,8 +401,17 @@ static std::pair<std::vector<size_t>, std::vector<Palette>>
 
 static std::pair<std::vector<size_t>, std::vector<Palette>>
     makePalsAsSpecified(std::vector<ColorSet> const &colorSets) {
-	// Convert the palette spec to actual palettes
 	std::vector<Palette> palettes(options.palSpec.size());
+
+	// If the image contains at least one transparent pixel, force transparency in the first slot of
+	// all palettes
+	if (options.hasTransparentPixels) {
+		for (Palette &pal : palettes) {
+			pal.colors[0] = Rgba::transparent;
+		}
+	}
+
+	// Convert the palette spec to actual palettes
 	bool gaveDeprecationWarning = false;
 	for (auto [spec, pal] : zip(options.palSpec, palettes)) {
 		bool skipFirst = false;
diff --git a/test/gfx/implicit-transparent.out.pal b/test/gfx/implicit-transparent.out.pal
new file mode 100644
index 0000000000000000000000000000000000000000..8d0318d1cad99366473abd5ad0578a4bf2e307db
GIT binary patch
literal 8
PcmZQ*V5pI2`2QaO32g%!

literal 0
HcmV?d00001