From 0b0be3539fe1f2cdc9c9caf7cc9831399565d6f4 Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Mon, 20 Mar 2023 13:57:31 +0300
Subject: [PATCH] Include mipmaps in texture memory usage

---
 libs/gfx/include/psemek/gfx/texture.hpp | 30 ++++++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/libs/gfx/include/psemek/gfx/texture.hpp b/libs/gfx/include/psemek/gfx/texture.hpp
index 5ddb343d..5352cfd4 100644
--- a/libs/gfx/include/psemek/gfx/texture.hpp
+++ b/libs/gfx/include/psemek/gfx/texture.hpp
@@ -82,10 +82,13 @@ namespace psemek::gfx
 		void mirrored_repeat();
 		void clamp();
 
+		bool uses_mipmaps() const { return uses_mipmaps_; }
+
 	protected:
 		GLuint id_ = 0;
 		GLint format_ = 0;
 		geom::vector<std::size_t, D> size_ = geom::vector<std::size_t, D>::zero();
+		bool uses_mipmaps_ = true;
 
 		explicit basic_texture(std::nullptr_t);
 	};
@@ -454,6 +457,7 @@ namespace psemek::gfx
 		bind();
 		gl::TexParameteri(Target, gl::TEXTURE_MIN_FILTER, gl::NEAREST);
 		gl::TexParameteri(Target, gl::TEXTURE_MAG_FILTER, gl::NEAREST);
+		uses_mipmaps_ = false;
 	}
 
 	template <std::size_t D, GLenum Target>
@@ -462,6 +466,7 @@ namespace psemek::gfx
 		bind();
 		gl::TexParameteri(Target, gl::TEXTURE_MIN_FILTER, gl::LINEAR);
 		gl::TexParameteri(Target, gl::TEXTURE_MAG_FILTER, gl::LINEAR);
+		uses_mipmaps_ = false;
 	}
 
 	template <std::size_t D, GLenum Target>
@@ -470,6 +475,7 @@ namespace psemek::gfx
 		bind();
 		gl::TexParameteri(Target, gl::TEXTURE_MIN_FILTER, gl::LINEAR_MIPMAP_LINEAR);
 		gl::TexParameteri(Target, gl::TEXTURE_MAG_FILTER, gl::LINEAR);
+		uses_mipmaps_ = true;
 	}
 
 
@@ -613,7 +619,29 @@ namespace psemek::gfx
 		auto size = texture.width() * texture.height() * texture.depth();
 		if (size == 0)
 			return 0;
-		return size * pixel_size(texture.internal_format());
+
+		float mipmap_factor = 1.f;
+		if (texture.uses_mipmaps())
+		{
+			switch (Target)
+			{
+			case gl::TEXTURE_1D:
+			case gl::TEXTURE_1D_ARRAY:
+				mipmap_factor = 2.f;
+				break;
+			case gl::TEXTURE_2D:
+			case gl::TEXTURE_2D_ARRAY:
+				mipmap_factor = 4.f / 3.f;
+				break;
+			case gl::TEXTURE_3D:
+				mipmap_factor = 8.f / 7.f;
+				break;
+			default:
+				break;
+			}
+		}
+
+		return std::ceil(mipmap_factor * size * pixel_size(texture.internal_format()));
 	}
 
 }