feat: Reorder, rename to NICE, fix casing

Author: koerismo

include/vtfpp/ImageConversion.h

@@ -375,7 +375,8 @@ enum class ResizeFilter {
 
 	// User-defined
 	KAISER = 100,
-	LANCZOS3 = 101,
+	/// Valve NICE filtering, equivalent to Lanczos-3
+	NICE = 101,
 };
 
 enum class ResizeMethod {

src/vtfpp/ImageConversion.cpp

@@ -1942,22 +1942,22 @@ std::vector<std::byte> ImageConversion::resizeImageData(std::span<const std::byt
 				stbir_set_filter_callbacks(&resize, KAISER_FILTER, KAISER_SUPPORT, KAISER_FILTER, KAISER_SUPPORT);
 				break;
 			}
-			case ResizeFilter::LANCZOS3: {
+			case ResizeFilter::NICE: {
 				static constexpr auto SINC = [](const float x) -> float {
 					if (x == 0.f) return 1.f;
 					const float a = x * math::pi_f32;
 					return sinf(a) / a;
 				};
-				// Normally you would max(1, inv_scale), but stb is weird and immediately un-scales the result when downsampling.
-				// See stb_image_resize2.h L2977
-				static constexpr auto LANCZOS3_SUPPORT = [](float inv_scale, void*) -> float {
-					return inv_scale * 3.f;
-				};
-				static constexpr auto LANCZOS3_FILTER = [](float x, float inv_scale, void*) -> float {
+				static constexpr auto NICE_FILTER = [](float x, float invScale, void*) -> float {
 					if (x >= 3.f || x <= -3.f) return 0.f;
 					return SINC(x) * SINC(x / 3.f);
 				};
-				stbir_set_filter_callbacks(&resize, LANCZOS3_FILTER, LANCZOS3_SUPPORT, LANCZOS3_FILTER, LANCZOS3_SUPPORT);
+				// Normally you would max(1, invScale), but stb is weird and immediately un-scales the result when downsampling.
+				// See stb_image_resize2.h L2977
+				static constexpr auto NICE_SUPPORT = [](float invScale, void*) -> float {
+					return invScale * 3.f;
+				};
+				stbir_set_filter_callbacks(&resize, NICE_FILTER, NICE_SUPPORT, NICE_FILTER, NICE_SUPPORT);
 				break;
 			}
 		}