From 03d3984ecd2c4e7c38b6a62b4b7a81bab69f8d40 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Mon, 2 Jul 2018 15:46:13 +0300
Subject: [PATCH] Explicitly define the number of mipmap levels in textures

Storage() no longer uses the minification filter to decide whether to
allocate mipmaps or not.  That functionality has been moved to image(),
specifically the version taking a Graphics::Image.
---
 source/texture1d.cpp   | 19 +++++++++++++------
 source/texture1d.h     |  3 ++-
 source/texture2d.cpp   | 19 +++++++++++++------
 source/texture2d.h     | 10 +++++++---
 source/texture3d.cpp   | 19 +++++++++++++------
 source/texture3d.h     | 10 +++++++---
 source/texturecube.cpp | 17 ++++++++++++-----
 source/texturecube.h   | 10 +++++++---
 8 files changed, 74 insertions(+), 33 deletions(-)

diff --git a/source/texture1d.cpp b/source/texture1d.cpp
index c5e57df2..a1ee418b 100644
--- a/source/texture1d.cpp
+++ b/source/texture1d.cpp
@@ -19,7 +19,7 @@ Texture1D::Texture1D():
 	static Require _req(MSP_texture1D);
 }
 
-void Texture1D::storage(PixelFormat fmt, unsigned wd)
+void Texture1D::storage(PixelFormat fmt, unsigned wd, unsigned lv)
 {
 	if(width>0)
 		throw invalid_operation("Texture1D::storage");
@@ -28,26 +28,30 @@ void Texture1D::storage(PixelFormat fmt, unsigned wd)
 
 	set_internal_format(fmt);
 	width = wd;
+	levels = get_n_levels();
+	if(lv)
+		levels = min(levels, lv);
 }
 
 void Texture1D::allocate(unsigned level)
 {
 	if(width==0)
 		throw invalid_operation("Texture1D::allocate");
+	if(level>=levels)
+		throw invalid_argument("Texture1D::allocate");
 	if(allocated&(1<<level))
 		return;
 
 	if(ARB_texture_storage)
 	{
-		unsigned n_levels = (is_mipmapped(min_filter) ? get_n_levels() : 1);
 		if(ARB_direct_state_access)
-			glTextureStorage1D(id, n_levels, ifmt, width);
+			glTextureStorage1D(id, levels, ifmt, width);
 		else
 		{
 			BindRestore _bind(this);
-			glTexStorage1D(target, n_levels, ifmt, width);
+			glTexStorage1D(target, levels, ifmt, width);
 		}
-		allocated |= (1<<n_levels)-1;
+		allocated |= (1<<levels)-1;
 	}
 	else
 	{
@@ -103,7 +107,10 @@ void Texture1D::image(const Graphics::Image &img, bool srgb)
 	unsigned w = img.get_width();
 	PixelFormat fmt = pixelformat_from_graphics(img.get_format());
 	if(width==0)
-		storage(storage_pixelformat_from_graphics(img.get_format(), srgb), w);
+	{
+		unsigned l = (is_mipmapped(min_filter) ? 0 : 1);
+		storage(storage_pixelformat_from_graphics(img.get_format(), srgb), w, l);
+	}
 	else if(w!=width)
 		throw incompatible_data("Texture1D::image");
 
diff --git a/source/texture1d.h b/source/texture1d.h
index 5e6f2549..506356c7 100644
--- a/source/texture1d.h
+++ b/source/texture1d.h
@@ -23,12 +23,13 @@ public:
 
 private:
 	unsigned width;
+	unsigned levels;
 	unsigned allocated;
 
 public:
 	Texture1D();
 
-	void storage(PixelFormat, unsigned);
+	void storage(PixelFormat, unsigned, unsigned = 0);
 	void allocate(unsigned);
 	void image(unsigned, PixelFormat, DataType, const void *);
 	void sub_image(unsigned, int, unsigned, PixelFormat, DataType, const void *);
diff --git a/source/texture2d.cpp b/source/texture2d.cpp
index 8d6e8471..44ee6406 100644
--- a/source/texture2d.cpp
+++ b/source/texture2d.cpp
@@ -46,7 +46,7 @@ Texture2D::~Texture2D()
 	set_manager(0);
 }
 
-void Texture2D::storage(PixelFormat fmt, unsigned wd, unsigned ht)
+void Texture2D::storage(PixelFormat fmt, unsigned wd, unsigned ht, unsigned lv)
 {
 	if(width>0)
 		throw invalid_operation("Texture2D::storage");
@@ -56,26 +56,30 @@ void Texture2D::storage(PixelFormat fmt, unsigned wd, unsigned ht)
 	set_internal_format(fmt);
 	width = wd;
 	height = ht;
+	levels = get_n_levels();
+	if(lv>0)
+		levels = min(levels, lv);
 }
 
 void Texture2D::allocate(unsigned level)
 {
 	if(width==0 || height==0)
 		throw invalid_operation("Texture2D::allocate");
+	if(level>=levels)
+		throw invalid_argument("Texture2D::allocate");
 	if(allocated&(1<<level))
 		return;
 
 	if(ARB_texture_storage)
 	{
-		unsigned n_levels = (is_mipmapped(min_filter) ? get_n_levels() : 1);
 		if(ARB_direct_state_access)
-			glTextureStorage2D(id, n_levels, ifmt, width, height);
+			glTextureStorage2D(id, levels, ifmt, width, height);
 		else
 		{
 			BindRestore _bind(this);
-			glTexStorage2D(target, n_levels, ifmt, width, height);
+			glTexStorage2D(target, levels, ifmt, width, height);
 		}
-		allocated |= (1<<n_levels)-1;
+		allocated |= (1<<levels)-1;
 	}
 	else
 	{
@@ -136,7 +140,10 @@ void Texture2D::image(const Graphics::Image &img, bool srgb, bool from_buffer)
 	unsigned h = img.get_height();
 	PixelFormat fmt = pixelformat_from_graphics(img.get_format());
 	if(width==0)
-		storage(storage_pixelformat_from_graphics(img.get_format(), srgb), w, h);
+	{
+		unsigned l = (is_mipmapped(min_filter) ? 0 : 1);
+		storage(storage_pixelformat_from_graphics(img.get_format(), srgb), w, h, l);
+	}
 	else if(w!=width || h!=height)
 		throw incompatible_data("Texture2D::image");
 
diff --git a/source/texture2d.h b/source/texture2d.h
index 1f8b5f7e..2a49eca5 100644
--- a/source/texture2d.h
+++ b/source/texture2d.h
@@ -33,15 +33,19 @@ private:
 
 	unsigned width;
 	unsigned height;
+	unsigned levels;
 	unsigned allocated;
 
 public:
 	Texture2D(ResourceManager * = 0);
 	virtual ~Texture2D();
 
-	/** Defines storage structure for the texture.  Must be called before an
-	image can be uploaded.  Once storage is defined, it can't be changed. */
-	void storage(PixelFormat fmt, unsigned wd, unsigned ht);
+	/** Defines storage structure for the texture.  If lv is zero, the number
+	of mipmap levels is automatically determined from storage dimensions.
+
+	Must be called before an image can be uploaded.  Once storage is defined,
+	it can't be changed. */
+	void storage(PixelFormat fmt, unsigned wd, unsigned ht, unsigned lv = 0);
 
 	/** Allocates storage for the texture.  The contents are initially
 	undefined.  If storage has already been allocated, does nothing. */
diff --git a/source/texture3d.cpp b/source/texture3d.cpp
index 5e1f9866..36fdfa0f 100644
--- a/source/texture3d.cpp
+++ b/source/texture3d.cpp
@@ -33,7 +33,7 @@ Texture3D::Texture3D():
 	static Require _req(EXT_texture3D);
 }
 
-void Texture3D::storage(PixelFormat fmt, unsigned wd, unsigned ht, unsigned dp)
+void Texture3D::storage(PixelFormat fmt, unsigned wd, unsigned ht, unsigned dp, unsigned lv)
 {
 	if(width>0)
 		throw invalid_operation("Texture3D::storage");
@@ -44,26 +44,30 @@ void Texture3D::storage(PixelFormat fmt, unsigned wd, unsigned ht, unsigned dp)
 	width = wd;
 	height = ht;
 	depth = dp;
+	levels = get_n_levels();
+	if(lv>0)
+		levels = min(levels, lv);
 }
 
 void Texture3D::allocate(unsigned level)
 {
 	if(width==0 || height==0 || depth==0)
 		throw invalid_operation("Texture3D::allocate");
+	if(level>=levels)
+		throw invalid_argument("Texture3D::allocate");
 	if(allocated&(1<<level))
 		return;
 
 	if(ARB_texture_storage)
 	{
-		unsigned n_levels = (is_mipmapped(min_filter) ? get_n_levels() : 1);
 		if(ARB_direct_state_access)
-			glTextureStorage3D(id, n_levels, ifmt, width, height, depth);
+			glTextureStorage3D(id, levels, ifmt, width, height, depth);
 		else
 		{
 			BindRestore _bind(this);
-			glTexStorage3D(target, n_levels, ifmt, width, height, depth);
+			glTexStorage3D(target, levels, ifmt, width, height, depth);
 		}
-		allocated |= (1<<n_levels)-1;
+		allocated |= (1<<levels)-1;
 	}
 	else
 	{
@@ -183,7 +187,10 @@ void Texture3D::image(const Graphics::Image &img, bool srgb)
 
 	PixelFormat fmt = pixelformat_from_graphics(img.get_format());
 	if(width==0)
-		storage(storage_pixelformat_from_graphics(img.get_format(), srgb), w, h, d);
+	{
+		unsigned l = (is_mipmapped(min_filter) ? 0 : 1);
+		storage(storage_pixelformat_from_graphics(img.get_format(), srgb), w, h, d, l);
+	}
 	else if(w!=width || h!=height || d!=depth)
 		throw incompatible_data("Texture3D::load_image");
 
diff --git a/source/texture3d.h b/source/texture3d.h
index cf336e52..437c852a 100644
--- a/source/texture3d.h
+++ b/source/texture3d.h
@@ -30,6 +30,7 @@ private:
 	unsigned width;
 	unsigned height;
 	unsigned depth;
+	unsigned levels;
 	unsigned allocated;
 
 protected:
@@ -37,9 +38,12 @@ protected:
 public:
 	Texture3D();
 
-	/** Defines storage structure for the texture.  Must be called before an
-	image can be uploaded.  Once storage is defined, it can't be changed. */
-	void storage(PixelFormat fmt, unsigned wd, unsigned ht, unsigned dp);
+	/** Defines storage structure for the texture.  If lv is zero, the number
+	of mipmap levels is automatically determined from storage dimensions.
+
+	Must be called before an image can be uploaded.  Once storage is defined,
+	it can't be changed. */
+	void storage(PixelFormat fmt, unsigned wd, unsigned ht, unsigned dp, unsigned lv = 0);
 
 	/** Allocates storage for the texture.  The contents are initially
 	undefined.  If storage has already been allocated, does nothing. */
diff --git a/source/texturecube.cpp b/source/texturecube.cpp
index b9a8f5dd..ee8c71c5 100644
--- a/source/texturecube.cpp
+++ b/source/texturecube.cpp
@@ -51,7 +51,7 @@ TextureCube::TextureCube():
 	static Require _req(ARB_texture_cube_map);
 }
 
-void TextureCube::storage(PixelFormat fmt, unsigned sz)
+void TextureCube::storage(PixelFormat fmt, unsigned sz, unsigned lv)
 {
 	if(size>0)
 		throw invalid_operation("TextureCube::storage");
@@ -60,21 +60,25 @@ void TextureCube::storage(PixelFormat fmt, unsigned sz)
 
 	set_internal_format(fmt);
 	size = sz;
+	levels = get_n_levels();
+	if(lv>0)
+		levels = min(levels, lv);
 }
 
 void TextureCube::allocate(unsigned level)
 {
 	if(size==0)
 		throw invalid_operation("TextureCube::allocate");
+	if(level>=levels)
+		throw invalid_argument("TextureCube::allocate");
 	if(allocated&(1<<level))
 		return;
 
 	if(ARB_texture_storage)
 	{
 		BindRestore _bind(this);
-		unsigned n_levels = (is_mipmapped(min_filter) ? get_n_levels() : 1);
-		glTexStorage2D(target, n_levels, ifmt, size, size);
-		allocated |= (1<<n_levels)-1;
+		glTexStorage2D(target, levels, ifmt, size, size);
+		allocated |= (1<<levels)-1;
 	}
 	else
 	{
@@ -156,7 +160,10 @@ void TextureCube::image(const Graphics::Image &img, bool srgb)
 
 	PixelFormat fmt = pixelformat_from_graphics(img.get_format());
 	if(size==0)
-		storage(storage_pixelformat_from_graphics(img.get_format(), srgb), w);
+	{
+		unsigned l = (is_mipmapped(min_filter) ? 0 : 1);
+		storage(storage_pixelformat_from_graphics(img.get_format(), srgb), w, l);
+	}
 	else if(w!=size || h!=size)
 		throw incompatible_data("TextureCube::image");
 
diff --git a/source/texturecube.h b/source/texturecube.h
index ea1c8296..0882a5e3 100644
--- a/source/texturecube.h
+++ b/source/texturecube.h
@@ -50,6 +50,7 @@ public:
 
 private:
 	unsigned size;
+	unsigned levels;
 	unsigned allocated;
 
 	static TextureCubeFace face_order[6];
@@ -59,9 +60,12 @@ private:
 public:
 	TextureCube();
 
-	/** Defines storage structure for the texture.  Must be called before an
-	image can be uploaded.  Once storage is defined, it can't be changed. */
-	void storage(PixelFormat fmt, unsigned size);
+	/** Defines storage structure for the texture.  If lv is zero, the number
+	of mipmap levels is automatically determined from storage dimensions.
+
+	Must be called before an image can be uploaded.  Once storage is defined,
+	it can't be changed. */
+	void storage(PixelFormat fmt, unsigned size, unsigned lv = 0);
 
 	/** Allocates storage for the cube faces.  The contents are initially
 	undefined.  If storage has already been allocated, does nothing. */
-- 
2.43.0