From: Mikko Rasa <tdb@tdb.fi>
Date: Wed, 10 Nov 2021 18:31:17 +0000 (+0200)
Subject: Account for mipmap levels when computing texture data sizes
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=commitdiff_plain;h=e2a707feb62c5df69884cca34d099dd2f7b7e4e2

Account for mipmap levels when computing texture data sizes

This isn't 100% accurate, but good enough for resource management.
---

diff --git a/source/backends/opengl/texture1d_backend.cpp b/source/backends/opengl/texture1d_backend.cpp
index a270468b..b8424872 100644
--- a/source/backends/opengl/texture1d_backend.cpp
+++ b/source/backends/opengl/texture1d_backend.cpp
@@ -64,8 +64,17 @@ void OpenGLTexture1D::sub_image(unsigned level, int x, unsigned wd, const void *
 
 size_t OpenGLTexture1D::get_data_size() const
 {
+	if(!id)
+		return 0;
+
 	unsigned width = static_cast<const Texture1D *>(this)->width;
-	return id ? width*get_pixel_size(storage_fmt) : 0;
+	unsigned levels = static_cast<const Texture1D *>(this)->levels;
+
+	size_t level_size = width*get_pixel_size(storage_fmt);
+	size_t total_size = level_size;
+	for(unsigned i=0; i<levels; ++i, level_size>>=2)
+		total_size += level_size;
+	return total_size;
 }
 
 } // namespace GL
diff --git a/source/backends/opengl/texture2d_backend.cpp b/source/backends/opengl/texture2d_backend.cpp
index 72962117..2f396df4 100644
--- a/source/backends/opengl/texture2d_backend.cpp
+++ b/source/backends/opengl/texture2d_backend.cpp
@@ -102,9 +102,18 @@ Resource::AsyncLoader *OpenGLTexture2D::load(IO::Seekable &io, const Resources *
 
 uint64_t OpenGLTexture2D::get_data_size() const
 {
+	if(!id)
+		return 0;
+
 	unsigned width = static_cast<const Texture2D *>(this)->width;
 	unsigned height = static_cast<const Texture2D *>(this)->height;
-	return id ? width*height*get_pixel_size(format) : 0;
+	unsigned levels = static_cast<const Texture2D *>(this)->levels;
+
+	size_t level_size = width*height*get_pixel_size(format);
+	size_t total_size = level_size;
+	for(unsigned i=0; i<levels; ++i, level_size>>=2)
+		total_size += level_size;
+	return total_size;
 }
 
 void OpenGLTexture2D::unload()
diff --git a/source/backends/opengl/texture2darray_backend.cpp b/source/backends/opengl/texture2darray_backend.cpp
index 610229ba..edca615d 100644
--- a/source/backends/opengl/texture2darray_backend.cpp
+++ b/source/backends/opengl/texture2darray_backend.cpp
@@ -10,5 +10,17 @@ OpenGLTexture2DArray::OpenGLTexture2DArray():
 	static Require _req(EXT_texture_array);
 }
 
+size_t OpenGLTexture2DArray::get_data_size() const
+{
+	if(!id)
+		return 0;
+
+	size_t level_size = width*height*get_pixel_size(format);
+	size_t total_size = level_size;
+	for(unsigned i=0; i<levels; ++i, level_size>>=2)
+		total_size += level_size*depth;
+	return total_size;
+}
+
 } // namespace GL
 } // namespace Msp
diff --git a/source/backends/opengl/texture2darray_backend.h b/source/backends/opengl/texture2darray_backend.h
index 42a33fc0..68a85386 100644
--- a/source/backends/opengl/texture2darray_backend.h
+++ b/source/backends/opengl/texture2darray_backend.h
@@ -10,6 +10,9 @@ class OpenGLTexture2DArray: public Texture3D
 {
 protected:
 	OpenGLTexture2DArray();
+
+public:
+	virtual std::size_t get_data_size() const;
 };
 
 using Texture2DArrayBackend = OpenGLTexture2DArray;
diff --git a/source/backends/opengl/texture3d_backend.cpp b/source/backends/opengl/texture3d_backend.cpp
index 0796472a..961dd7e7 100644
--- a/source/backends/opengl/texture3d_backend.cpp
+++ b/source/backends/opengl/texture3d_backend.cpp
@@ -76,10 +76,19 @@ bool OpenGLTexture3D::is_array() const
 
 size_t OpenGLTexture3D::get_data_size() const
 {
+	if(!id)
+		return 0;
+
 	unsigned width = static_cast<const Texture3D *>(this)->width;
 	unsigned height = static_cast<const Texture3D *>(this)->height;
 	unsigned depth = static_cast<const Texture3D *>(this)->depth;
-	return id ? width*height*depth*get_pixel_size(storage_fmt) : 0;
+	unsigned levels = static_cast<const Texture3D *>(this)->levels;
+
+	size_t level_size = width*height*depth*get_pixel_size(format);
+	size_t total_size = level_size;
+	for(unsigned i=0; i<levels; ++i, level_size>>=2)
+		total_size += level_size;
+	return total_size;
 }
 
 } // namespace GL
diff --git a/source/backends/opengl/texturecube_backend.cpp b/source/backends/opengl/texturecube_backend.cpp
index 2b9e09a9..1cc3f837 100644
--- a/source/backends/opengl/texturecube_backend.cpp
+++ b/source/backends/opengl/texturecube_backend.cpp
@@ -77,8 +77,17 @@ void OpenGLTextureCube::sub_image(unsigned face, unsigned level, int x, int y, u
 
 size_t OpenGLTextureCube::get_data_size() const
 {
+	if(!id)
+		return 0;
+
 	unsigned size = static_cast<const TextureCube *>(this)->size;
-	return id ? size*size*6*get_pixel_size(storage_fmt) : 0;
+	unsigned levels = static_cast<const TextureCube *>(this)->levels;
+
+	size_t level_size = size*size*get_pixel_size(storage_fmt);
+	size_t total_size = level_size;
+	for(unsigned i=0; i<levels; ++i, level_size>>=2)
+		total_size += level_size;
+	return total_size;
 }