Add uniqueness assertion for plugin slugs, fix PolarityValueLight alpha

include/components.hpp

@@ -402,7 +402,7 @@ struct ColorValueLight : ValueLight {
 	void setValue(float v) {
 		v = sqrtBipolar(v);
 		color = baseColor;
-		color.a = clampf(v * baseColor.a, 0.0, 1.0);
+		color.a *= clampf(v, 0.0, 1.0);
 	}
 };
 
@@ -430,7 +430,7 @@ struct PolarityLight : ValueLight {
 	void setValue(float v) {
 		v = sqrtBipolar(v);
 		color = (v >= 0.0) ? posColor : negColor;
-		color.a = clampf(fabsf(v) * color.a, 0.0, 1.0);
+		color.a *= clampf(fabsf(v), 0.0, 1.0);
 	}
 };
 

src/plugin.cpp

@@ -89,6 +89,11 @@ static int loadPlugin(std::string path) {
 	plugin->handle = handle;
 	initCallback(plugin);
 
+	// Check that this is a unique slug
+	for (Plugin *otherPlugin : gPlugins) {
+		assert(plugin->slug != otherPlugin->slug);
+	}
+
 	// Add plugin to list
 	gPlugins.push_back(plugin);
 	fprintf(stderr, "Loaded plugin %s\n", libraryFilename.c_str());