- Added GTX_texture: levels function

glm/gtx/texture.hpp

@@ -14,6 +14,8 @@
 
 // Dependency:
 #include "../glm.hpp"
+#include "../gtc/integer.hpp"
+#include "../gtx/component_wise.hpp"
 
 #ifndef GLM_ENABLE_EXPERIMENTAL
 #	error "GLM: GLM_GTX_texture is an experimental extension and may change in the future. Use #define GLM_ENABLE_EXPERIMENTAL before including it, if you really want to use it."
@@ -28,17 +30,17 @@ namespace glm
 	/// @addtogroup gtx_texture
 	/// @{
 
+	/// Compute the number of mipmaps levels necessary to create a mipmap complete texture
+	///
+	/// @param Extent Extent of the texture base level mipmap
+	/// @tparam L Integer between 1 and 4 included that qualify the dimension of the vector
+	/// @tparam T Floating-point or signed integer scalar types
+	/// @tparam Q Value from qualifier enum
+	template <length_t L, typename T, qualifier Q>
+	T levels(vec<L, T, Q> const& Extent);
 
 	/// @}
 }// namespace glm
 
 #include "texture.inl"
 
-/// @ref gtx_texture
-/// @file glm/gtx/texture.inl
-
-namespace glm
-{
-
-}//namespace glm
-

glm/gtx/texture.inl

@@ -3,6 +3,16 @@
 
 namespace glm
 {
+	template <length_t L, typename T, qualifier Q>
+	inline T levels(vec<L, T, Q> const& Extent)
+	{
+		return glm::log2(compMax(Extent)) + static_cast<T>(1);
+	}
 
+	template <typename T>
+	inline T levels(T Extent)
+	{
+		return vec<1, T, defaultp>(Extent).x;
+	}
 }//namespace glm