Add ColourRGBA::Grey constructing method to simplify use of grey-scale colours.

Use symbolic constants for colour components, fixing 'magic number' warnings.

1 files changed, 5 insertions, 1 deletions

diff --git a/src/Geometry.h b/src/Geometry.h
index a9daa5516..d02a25bbb 100644
--- a/src/Geometry.h
+++ b/src/Geometry.h
@@ -182,7 +182,7 @@ public:
 	constexpr explicit ColourRGBA(int co_ = 0) noexcept : co(co_) {
 	}
 
-	constexpr ColourRGBA(unsigned int red, unsigned int green, unsigned int blue, unsigned int alpha= maximumByte) noexcept :
+	constexpr ColourRGBA(unsigned int red, unsigned int green, unsigned int blue, unsigned int alpha=maximumByte) noexcept :
 		ColourRGBA(red | (green << 8) | (blue << 16) | (alpha << 24)) {
 	}
 
@@ -194,6 +194,10 @@ public:
 		return ColourRGBA(co_ | (maximumByte << 24));
 	}
 
+	static constexpr ColourRGBA Grey(unsigned int grey, unsigned int alpha=maximumByte) noexcept {
+		return ColourRGBA(grey, grey, grey, alpha);
+	}
+
 	static constexpr ColourRGBA FromIpRGB(intptr_t co_) noexcept {
 		const int rgb = co_ & rgbMask;
 		return ColourRGBA(rgb | (maximumByte << 24));