From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 6 Feb 2021 13:27:53 +0000 (+0200)
Subject: Support samplers as independent objects
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=6cbcaf877f0be27b4d921d1c182f5e21d4662268;p=libs%2Fgl.git

Support samplers as independent objects
---

diff --git a/source/sampler.cpp b/source/sampler.cpp
index 9476ffe9..cc54901b 100644
--- a/source/sampler.cpp
+++ b/source/sampler.cpp
@@ -14,6 +14,18 @@ using namespace std;
 namespace Msp {
 namespace GL {
 
+Sampler::Sampler():
+	owner(0)
+{
+	init();
+
+	Require _req(ARB_sampler_objects);
+	if(ARB_direct_state_access)
+		glCreateSamplers(1, &id);
+	else
+		glGenSamplers(1, &id);
+}
+
 Sampler::Sampler(const Texture &tex):
 	id(0),
 	owner(&tex)
@@ -39,16 +51,25 @@ void Sampler::init()
 
 void Sampler::update_parameter(int mask) const
 {
-	if(!owner->get_id() || (!ARB_direct_state_access && TexUnit::current().get_texture()!=owner))
+	if(owner)
 	{
-		TexUnit *unit = TexUnit::find_unit(owner);
-		if(!unit)
+		if(!owner->get_id())
 		{
 			dirty_params |= mask;
 			return;
 		}
 
-		unit->bind();
+		if(!ARB_direct_state_access && TexUnit::current().get_texture()!=owner)
+		{
+			TexUnit *unit = TexUnit::find_unit(owner);
+			if(!unit)
+			{
+				dirty_params |= mask;
+				return;
+			}
+
+			unit->bind();
+		}
 	}
 
 	if(mask&MIN_FILTER)
@@ -73,7 +94,9 @@ void Sampler::update_parameter(int mask) const
 
 void Sampler::set_parameter_i(unsigned param, int value) const
 {
-	if(ARB_direct_state_access)
+	if(id)
+		glSamplerParameteri(id, param, value);
+	else if(ARB_direct_state_access)
 		glTextureParameteri(owner->get_id(), param, value);
 	else
 		glTexParameteri(owner->get_target(), param, value);
@@ -81,7 +104,9 @@ void Sampler::set_parameter_i(unsigned param, int value) const
 
 void Sampler::set_parameter_f(unsigned param, float value) const
 {
-	if(ARB_direct_state_access)
+	if(id)
+		glSamplerParameterf(id, param, value);
+	else if(ARB_direct_state_access)
 		glTextureParameterf(owner->get_id(), param, value);
 	else
 		glTexParameterf(owner->get_target(), param, value);
@@ -160,16 +185,36 @@ void Sampler::set_compare(Predicate f)
 void Sampler::bind_to(unsigned i) const
 {
 	TexUnit &unit = TexUnit::get_unit(i);
-	if(owner!=unit.get_texture())
+	if(owner && owner!=unit.get_texture())
 		throw invalid_operation("Sampler::bind_to");
 
-	if(dirty_params)
+	const Sampler *cur = unit.get_sampler();
+	if(unit.set_sampler(this))
 	{
-		update_parameter(dirty_params);
-		dirty_params = 0;
+		if(!owner || (cur && cur->id))
+			glBindSampler(i, id);
+
+		if(dirty_params)
+		{
+			update_parameter(dirty_params);
+			dirty_params = 0;
+		}
 	}
 }
 
+const Sampler *Sampler::current(unsigned i)
+{
+	return TexUnit::get_unit(i).get_sampler();
+}
+
+void Sampler::unbind_from(unsigned i)
+{
+	TexUnit &unit = TexUnit::get_unit(i);
+	const Sampler *cur = unit.get_sampler();
+	if(unit.set_sampler(0) && cur->id)
+		glBindSampler(i, 0);
+}
+
 void Sampler::unload()
 {
 	// TODO check which params actually need refreshing
diff --git a/source/sampler.h b/source/sampler.h
index 255d1da4..e1e9bec5 100644
--- a/source/sampler.h
+++ b/source/sampler.h
@@ -149,6 +149,10 @@ public:
 	void bind() const { bind_to(0); }
 	void bind_to(unsigned) const;
 
+	static const Sampler *current(unsigned = 0);
+	static void unbind() { unbind_from(0); }
+	static void unbind_from(unsigned);
+
 	void unload();
 };
 
diff --git a/source/texture.cpp b/source/texture.cpp
index ab570048..381a0a59 100644
--- a/source/texture.cpp
+++ b/source/texture.cpp
@@ -238,7 +238,8 @@ void Texture::bind_to(unsigned i) const
 			glBindTexture(target, id);
 		}
 
-		default_sampler.bind_to(i);
+		if(!unit.get_sampler())
+			default_sampler.bind_to(i);
 	}
 }
 
@@ -260,6 +261,9 @@ void Texture::unbind_from(unsigned i)
 			unit.bind();
 			glBindTexture(cur->target, 0);
 		}
+
+		if(unit.get_sampler()==&cur->default_sampler)
+			Sampler::unbind_from(i);
 	}
 }
 
diff --git a/source/texture3d.cpp b/source/texture3d.cpp
index 667f8c31..1f62e050 100644
--- a/source/texture3d.cpp
+++ b/source/texture3d.cpp
@@ -142,22 +142,11 @@ void Texture3D::image(const Graphics::Image &img, unsigned lv)
 {
 	unsigned w = img.get_width();
 	unsigned h = img.get_height();
-	unsigned d = 1;
 
-	if(depth)
-	{
-		if(h%depth)
-			throw incompatible_data("Texture3D::load_image");
-		h /= depth;
-		d = depth;
-	}
-	else
-	{
-		if(h%w)
-			throw incompatible_data("Texture3D::load_image");
-		d = h/w;
-		h = w;
-	}
+	if(h%w)
+		throw incompatible_data("Texture3D::load_image");
+	unsigned d = h/w;
+	h = w;
 
 	PixelFormat fmt = pixelformat_from_image(img);
 	if(width==0)
diff --git a/source/texturing.cpp b/source/texturing.cpp
index c30216f1..ab5d39b4 100644
--- a/source/texturing.cpp
+++ b/source/texturing.cpp
@@ -21,7 +21,7 @@ int Texturing::find_free_unit(const string &name_hint) const
 	max_unit -= min(max_unit/4, 8U);
 	unsigned initial_unit = (name_hint.empty() ? 0 : hash32(name_hint)%max_unit);
 	unsigned unit = initial_unit;
-	while(get_attached_texture(unit))
+	while(get_attached_texture(unit) || get_attached_sampler(unit))
 	{
 		unit = (unit+1)%max_unit;
 		if(unit==initial_unit)
@@ -31,34 +31,40 @@ int Texturing::find_free_unit(const string &name_hint) const
 	return unit;
 }
 
-void Texturing::attach(unsigned attch, const Texture &tex)
+void Texturing::attach(unsigned attch, const Texture &tex, const Sampler *samp)
 {
-	set_attachment(attch, &tex);
+	set_attachment(attch, &tex, samp);
+}
+
+void Texturing::attach(unsigned attch, const Sampler &samp)
+{
+	set_attachment(attch, 0, &samp);
 }
 
 void Texturing::detach(unsigned attch)
 {
-	set_attachment(attch, 0);
+	set_attachment(attch, 0, 0);
 }
 
-void Texturing::set_attachment(unsigned unit, const Texture *tex)
+void Texturing::set_attachment(unsigned unit, const Texture *tex, const Sampler *samp)
 {
 	if(unit>=TexUnit::get_n_units())
 		throw out_of_range("Texturing::set_attachment");
 
-	if(tex)
+	if(tex || samp)
 	{
 		vector<Attachment>::iterator i;
 		for(i=attachments.begin(); (i!=attachments.end() && i->unit<=unit); ++i)
 			if(i->unit==unit)
 			{
 				i->texture = tex;
+				i->sampler = samp;
 				if(current()==this)
-					tex->bind_to(unit);
+					bind_attachment(*i);
 				return;
 			}
 
-		attachments.insert(i, Attachment(unit, tex));
+		attachments.insert(i, Attachment(unit, tex, samp));
 		if(current()==this)
 			tex->bind_to(unit);
 	}
@@ -69,7 +75,7 @@ void Texturing::set_attachment(unsigned unit, const Texture *tex)
 			{
 				attachments.erase(i);
 				if(current()==this)
-					Texture::unbind_from(unit);
+					unbind_attachment(unit);
 				return;
 			}
 	}
@@ -83,6 +89,14 @@ const Texture *Texturing::get_attached_texture(unsigned unit) const
 	return 0;
 }
 
+const Sampler *Texturing::get_attached_sampler(unsigned unit) const
+{
+	for(vector<Attachment>::const_iterator i=attachments.begin(); (i!=attachments.end() && i->unit<=unit); ++i)
+		if(i->unit==unit)
+			return i->sampler;
+	return 0;
+}
+
 void Texturing::bind() const
 {
 	const Texturing *old = current();
@@ -96,14 +110,14 @@ void Texturing::bind() const
 			{
 				if(i!=attachments.end() && (j==old->attachments.end() || i->unit<=j->unit))
 				{
-					i->texture->bind_to(i->unit);
+					bind_attachment(*i);
 					if(j!=old->attachments.end() && j->unit==i->unit)
 						++j;
 					++i;
 				}
 				else
 				{
-					Texture::unbind_from(j->unit);
+					unbind_attachment(j->unit);
 					++j;
 				}
 			}
@@ -111,25 +125,41 @@ void Texturing::bind() const
 		else
 		{
 			for(vector<Attachment>::const_iterator i=attachments.begin(); i!=attachments.end(); ++i)
-				i->texture->bind_to(i->unit);
+				bind_attachment(*i);
 		}
 	}
 }
 
+void Texturing::bind_attachment(const Attachment &attch) const
+{
+	if(attch.sampler)
+		attch.sampler->bind_to(attch.unit);
+	else
+		Sampler::unbind_from(attch.unit);
+	attch.texture->bind_to(attch.unit);
+}
+
 void Texturing::unbind()
 {
 	const Texturing *old = current();
 	if(set_current(0))
 	{
 		for(vector<Attachment>::const_iterator i=old->attachments.begin(); i!=old->attachments.end(); ++i)
-			Texture::unbind_from(i->unit);
+			unbind_attachment(i->unit);
 	}
 }
 
+void Texturing::unbind_attachment(unsigned unit)
+{
+	Texture::unbind_from(unit);
+	Sampler::unbind_from(unit);
+}
+
 
-Texturing::Attachment::Attachment(unsigned u, const Texture *t):
+Texturing::Attachment::Attachment(unsigned u, const Texture *t, const Sampler *s):
 	unit(u),
-	texture(t)
+	texture(t),
+	sampler(s)
 { }
 
 } // namespace GL
diff --git a/source/texturing.h b/source/texturing.h
index cba77e3f..0da3eae4 100644
--- a/source/texturing.h
+++ b/source/texturing.h
@@ -16,8 +16,9 @@ private:
 	{
 		unsigned unit;
 		const Texture *texture;
+		const Sampler *sampler;
 
-		Attachment(unsigned, const Texture *);
+		Attachment(unsigned, const Texture *, const Sampler *);
 	};
 
 	std::vector<Attachment> attachments;
@@ -26,16 +27,22 @@ public:
 	~Texturing();
 
 	int find_free_unit(const std::string & = std::string()) const;
-	void attach(unsigned, const Texture &);
+	void attach(unsigned, const Texture &, const Sampler * = 0);
+	void attach(unsigned, const Sampler &);
 	void detach(unsigned);
 private:
-	void set_attachment(unsigned, const Texture *);
+	void set_attachment(unsigned, const Texture *, const Sampler *);
 public:
 	const Texture *get_attached_texture(unsigned) const;
+	const Sampler *get_attached_sampler(unsigned) const;
 
 	void bind() const;
 
 	static void unbind();
+
+private:
+	void bind_attachment(const Attachment &) const;
+	static void unbind_attachment(unsigned);
 };
 
 } // namespace GL
diff --git a/source/texunit.cpp b/source/texunit.cpp
index 493a7611..0659d615 100644
--- a/source/texunit.cpp
+++ b/source/texunit.cpp
@@ -3,6 +3,7 @@
 #include <msp/gl/extensions/arb_vertex_shader.h>
 #include "gl.h"
 #include "misc.h"
+#include "texture.h"
 #include "texunit.h"
 
 using namespace std;
@@ -14,7 +15,8 @@ vector<TexUnit> TexUnit::units;
 TexUnit *TexUnit::cur_unit = 0;
 
 TexUnit::TexUnit():
-	texture(0)
+	texture(0),
+	sampler(0)
 { }
 
 bool TexUnit::set_texture(const Texture *tex)
@@ -24,6 +26,13 @@ bool TexUnit::set_texture(const Texture *tex)
 	return result;
 }
 
+bool TexUnit::set_sampler(const Sampler *samp)
+{
+	bool result = (samp!=sampler);
+	sampler = samp;
+	return result;
+}
+
 void TexUnit::bind()
 {
 	if(cur_unit!=this && (cur_unit || index))
diff --git a/source/texunit.h b/source/texunit.h
index 6bd2f82d..6253d8d9 100644
--- a/source/texunit.h
+++ b/source/texunit.h
@@ -6,8 +6,7 @@
 namespace Msp {
 namespace GL {
 
-class TexEnv;
-class TexGen;
+class Sampler;
 class Texture;
 
 /**
@@ -18,6 +17,7 @@ class TexUnit
 private:
 	unsigned index;
 	const Texture *texture;
+	const Sampler *sampler;
 
 	static std::vector<TexUnit> units;
 	static TexUnit *cur_unit;
@@ -28,6 +28,8 @@ public:
 	unsigned get_index() const { return index; }
 	bool set_texture(const Texture *);
 	const Texture *get_texture() const { return texture; }
+	bool set_sampler(const Sampler *);
+	const Sampler *get_sampler() const { return sampler; }
 	void bind();
 
 	static unsigned get_n_units();