Always bind textures in a specific texture unit

This eliminates one level of global state, simplifying the API and
offering new optimization possibilities.  Since single-texturing is a
common use case, the parameterless bind/unbind functions have been left
in but changed to operate on unit 0.

diff --git a/source/environmentmap.cpp b/source/environmentmap.cpp
index 8a1dfe399acfae7260c79aa33022a2662337f7b9..be0bf4109f9c64e6f27796ab1c5b865385624fd1 100644 (file)
--- a/source/environmentmap.cpp
+++ b/source/environmentmap.cpp
@@ -87,14 +87,12 @@ void EnvironmentMap::render(Renderer &renderer, const Tag &tag) const
        shdata.uniform_matrix3("env_eye_matrix", env_mdata);
 
        env_tex.bind_to(4);
-       TexUnit::activate(0);
 
        Renderer::Push _push_rend(renderer);
        renderer.add_shader_data(shdata);
        renderer.render(renderable, tag);
 
        env_tex.unbind_from(4);
-       TexUnit::activate(0);
 }
 
 } // namespace GL

diff --git a/source/shadowmap.cpp b/source/shadowmap.cpp
index 91c056fe147cc4c994100b5a1aa1e2ec8534c730..86715fca956ed549c5723a110a86f2bc4e6c94c0 100644 (file)
--- a/source/shadowmap.cpp
+++ b/source/shadowmap.cpp
@@ -153,20 +153,18 @@ void ShadowMap::render(Renderer &renderer, const Tag &tag) const
        tg_s.set_plane(Vector4(matrix[0]/diam, matrix[4]/diam, matrix[8]/diam, matrix[12]/diam+0.5f));
        tg_t.set_plane(Vector4(matrix[1]/diam, matrix[5]/diam, matrix[9]/diam, matrix[13]/diam+0.5f));
        tg_r.set_plane(Vector4(-matrix[2]/diam, -matrix[6]/diam, -matrix[10]/diam, 0.5f-matrix[14]/diam-depth_bias/size));
-       tg_s.bind_to(SCOORD);
-       tg_t.bind_to(TCOORD);
-       tg_r.bind_to(RCOORD);
-       TexUnit::activate(0);
+       tg_s.bind_to(unit, SCOORD);
+       tg_t.bind_to(unit, TCOORD);
+       tg_r.bind_to(unit, RCOORD);
 
        Renderer::Push _push_rend(renderer);
        renderer.add_shader_data(shdata);
        renderer.render(renderable, tag);
 
        Texture::unbind_from(unit);
-       TexGen::unbind_from(SCOORD);
-       TexGen::unbind_from(TCOORD);
-       TexGen::unbind_from(RCOORD);
-       TexUnit::activate(0);
+       TexGen::unbind_from(unit, SCOORD);
+       TexGen::unbind_from(unit, TCOORD);
+       TexGen::unbind_from(unit, RCOORD);
 }
 
 } // namespace GL

diff --git a/source/texenv.cpp b/source/texenv.cpp
index c1585391bdcddc04ce809f25ce767001a046116f..ff77e8cead0d6afb77fe51fd837b960377be8096 100644 (file)
--- a/source/texenv.cpp
+++ b/source/texenv.cpp
@@ -11,35 +11,39 @@ TexEnv::TexEnv():
 void TexEnv::set_mode(TexEnvMode m)
 {
        mode = m;
-       if(current()==this)
+       if(TexUnit::current().get_texenv()==this)
                glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, mode);
 }
 
 void TexEnv::set_color(const Color &c)
 {
        color = c;
-       if(current()==this)
+       if(TexUnit::current().get_texenv()==this)
                glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, &color.r);
 }
 
-void TexEnv::bind() const
+void TexEnv::bind_to(unsigned i) const
 {
-       if(TexUnit::current().set_texenv(this))
+       TexUnit &unit = TexUnit::get_unit(i);
+       if(unit.set_texenv(this))
        {
+               unit.bind();
                glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, mode);
                glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, &color.r);
        }
 }
 
-const TexEnv *TexEnv::current()
+const TexEnv *TexEnv::current(unsigned i)
 {
-       return TexUnit::current().get_texenv();
+       return TexUnit::get_unit(i).get_texenv();
 }
 
-void TexEnv::unbind()
+void TexEnv::unbind_from(unsigned i)
 {
-       if(TexUnit::current().set_texenv(0))
+       TexUnit &unit = TexUnit::get_unit(i);
+       if(unit.set_texenv(0))
        {
+               unit.bind();
                Color black(0, 0, 0, 0);
                glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, MODULATE);
                glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, &black.r);

diff --git a/source/texenv.h b/source/texenv.h
index 5ed05d6c7e0d24343e6fe9dbeba3675613208ead..1327bb850de64999e297f504b82489811164104c 100644 (file)
--- a/source/texenv.h
+++ b/source/texenv.h
@@ -29,10 +29,12 @@ public:
        void set_color(const Color &);
        TexEnvMode get_mode() const { return mode; }
        const Color &get_color() const { return color; }
-       void bind() const;
+       void bind() const { bind_to(0); }
+       void bind_to(unsigned) const;
 
-       static const TexEnv *current();
-       static void unbind();
+       static const TexEnv *current(unsigned = 0);
+       static void unbind() { unbind_from(0); }
+       static void unbind_from(unsigned);
 };
 
 } // namespace GL

diff --git a/source/texgen.cpp b/source/texgen.cpp
index e9a75d7a0ea27286287ef78ae0e0b2b5402bd3bb..eb6179d08ef680e8732e544d7692533cec649a90 100644 (file)
--- a/source/texgen.cpp
+++ b/source/texgen.cpp
@@ -22,10 +22,12 @@ void TexGen::set_plane(const Vector4 &p)
        plane = p;
 }
 
-void TexGen::bind_to(TexCoordComponent c) const
+void TexGen::bind_to(unsigned i, TexCoordComponent c) const
 {
-       if(TexUnit::current().set_texgen(coord_index(c), this))
+       TexUnit &unit = TexUnit::get_unit(i);
+       if(unit.set_texgen(coord_index(c), this))
        {
+               unit.bind();
                glTexGeni(c, GL_TEXTURE_GEN_MODE, mode);
                if(mode==EYE_LINEAR)
                        glTexGenfv(c, GL_EYE_PLANE, &plane.x);
@@ -35,14 +37,15 @@ void TexGen::bind_to(TexCoordComponent c) const
        }
 }
 
-const TexGen *TexGen::current(TexCoordComponent c)
+const TexGen *TexGen::current(unsigned i, TexCoordComponent c)
 {
-       return TexUnit::current().get_texgen(coord_index(c));
+       return TexUnit::get_unit(i).get_texgen(coord_index(c));
 }
 
-void TexGen::unbind_from(TexCoordComponent c)
+void TexGen::unbind_from(unsigned i, TexCoordComponent c)
 {
-       if(TexUnit::current().set_texgen(coord_index(c), 0))
+       TexUnit &unit = TexUnit::get_unit(i);
+       if(unit.set_texgen(coord_index(c), 0))
                disable(GL_TEXTURE_GEN_S+coord_index(c));
 }
 

diff --git a/source/texgen.h b/source/texgen.h
index bb076c629ddb2ea7ea50d8b1b1f1cb64e1b11391..c69df6386fceb0036eb99e8ebfa6ddf5280d6cce 100644 (file)
--- a/source/texgen.h
+++ b/source/texgen.h
@@ -35,10 +35,13 @@ public:
        void set_mode(TexGenMode);
        void set_plane(const Vector4 &);
 
-       void bind_to(TexCoordComponent) const;
+       void bind_to(TexCoordComponent c) const { bind_to(0, c); }
+       void bind_to(unsigned, TexCoordComponent) const;
 
-       static const TexGen *current(TexCoordComponent);
-       static void unbind_from(TexCoordComponent);
+       static const TexGen *current(TexCoordComponent c) { return current(0, c); }
+       static const TexGen *current(unsigned, TexCoordComponent);
+       static void unbind_from(TexCoordComponent c) { unbind_from(0, c); }
+       static void unbind_from(unsigned, TexCoordComponent);
 private:
        static unsigned coord_index(TexCoordComponent);
 };

diff --git a/source/texture.cpp b/source/texture.cpp
index aeea2818debfaaf03345da191b95d7cf39053dc9..f6b5f8e4be06f6e0706de648d9a8f30da78bff56 100644 (file)
--- a/source/texture.cpp
+++ b/source/texture.cpp
@@ -64,7 +64,7 @@ Texture::~Texture()
 
 void Texture::update_parameter(int mask) const
 {
-       if(current()==this)
+       if(TexUnit::current().get_texture()==this)
        {
                if(mask&MIN_FILTER)
                        glTexParameteri(target, GL_TEXTURE_MIN_FILTER, min_filter);
@@ -162,18 +162,18 @@ void Texture::set_compare_func(Predicate f)
        update_parameter(COMPARE_FUNC);
 }
 
-void Texture::bind() const
+void Texture::bind_to(unsigned i) const
 {
-       const Texture *cur = TexUnit::current().get_texture();
-       if(cur!=this)
+       TexUnit &unit = TexUnit::get_unit(i);
+       const Texture *cur = unit.get_texture();
+       if(unit.set_texture(this))
        {
+               unit.bind();
                if(cur && cur->target!=target)
                        glDisable(cur->target);
                if(!cur || cur->target!=target)
                        glEnable(target);
-
                glBindTexture(target, id);
-               TexUnit::current().set_texture(this);
 
                if(dirty_params)
                {
@@ -183,32 +183,21 @@ void Texture::bind() const
        }
 }
 
-void Texture::bind_to(unsigned i) const
-{
-       TexUnit::activate(i);
-       bind();
-}
-
-const Texture *Texture::current()
+const Texture *Texture::current(unsigned i)
 {
-       return TexUnit::current().get_texture();
-}
-
-void Texture::unbind()
-{
-       const Texture *cur = TexUnit::current().get_texture();
-       if(!cur)
-               return;
-
-       glBindTexture(cur->target, 0);
-       glDisable(cur->target);
-       TexUnit::current().set_texture(0);
+       return TexUnit::get_unit(i).get_texture();
 }
 
 void Texture::unbind_from(unsigned i)
 {
-       TexUnit::activate(i);
-       unbind();
+       TexUnit &unit = TexUnit::get_unit(i);
+       const Texture *cur = unit.get_texture();
+       if(unit.set_texture(0))
+       {
+               unit.bind();
+               glBindTexture(cur->target, 0);
+               glDisable(cur->target);
+       }
 }
 
 

diff --git a/source/texture.h b/source/texture.h
index 6b8117fe4f7d11b1c385e174cb343da29f48d909..c091c884cacfd592833120b785c7f83ff2fe303e 100644 (file)
--- a/source/texture.h
+++ b/source/texture.h
@@ -149,11 +149,11 @@ public:
        GLenum get_target() const { return target; }
        unsigned get_id() const { return id; }
 
-       void bind() const;
+       void bind() const { bind_to(0); }
        void bind_to(unsigned) const;
 
-       static const Texture *current();
-       static void unbind();
+       static const Texture *current(unsigned = 0);
+       static void unbind() { unbind_from(0); }
        static void unbind_from(unsigned);
 };
 

diff --git a/source/texturing.cpp b/source/texturing.cpp
index 880f3f0751a40df642d4b7d713d3497c94476da2..1c8410c57a6bff3ee9388805964a1cca0876981c 100644 (file)
--- a/source/texturing.cpp
+++ b/source/texturing.cpp
@@ -47,22 +47,20 @@ void Texturing::set_attachment(unsigned attch, const Texture *tex, const TexEnv
 void Texturing::bind_attachment(unsigned i) const
 {
        const Attachment &attch = attachments[i];
-       TexUnit::activate(i);
        if(attch.tex)
-               attch.tex->bind();
+               attch.tex->bind_to(i);
        else
-               Texture::unbind();
+               Texture::unbind_from(i);
        if(attch.env)
-               attch.env->bind();
+               attch.env->bind_to(i);
        else
-               TexEnv::unbind();
+               TexEnv::unbind_from(i);
 }
 
 void Texturing::unbind_attachment(unsigned i)
 {
-       TexUnit::activate(i);
-       Texture::unbind();
-       TexEnv::unbind();
+       Texture::unbind_from(i);
+       TexEnv::unbind_from(i);
 }
 
 void Texturing::bind() const

diff --git a/source/texunit.cpp b/source/texunit.cpp
index 2b3418fee43cb4fe7a7f0276ad2f6ffdb2d602ea..982e524e0189fa74a10181c9a2ff7f7014e8746e 100644 (file)
--- a/source/texunit.cpp
+++ b/source/texunit.cpp
@@ -49,6 +49,13 @@ const TexGen *TexUnit::get_texgen(unsigned i)
        return texgen[i];
 }
 
+void TexUnit::bind()
+{
+       if(cur_unit!=this && (cur_unit || index))
+               glActiveTexture(GL_TEXTURE0+index);
+       cur_unit = this;
+}
+
 unsigned TexUnit::get_n_units()
 {
        static int count = -1;
@@ -64,12 +71,12 @@ unsigned TexUnit::get_n_units()
        return count;
 }
 
-TexUnit &TexUnit::activate(unsigned n)
+TexUnit &TexUnit::get_unit(unsigned n)
 {
        if(n>0)
                static Require _req(ARB_multitexture);
        if(n>=get_n_units())
-               throw out_of_range("TexUnit::activate");
+               throw out_of_range("TexUnit::get_unit");
 
        if(units.size()<=n)
        {
@@ -79,17 +86,13 @@ TexUnit &TexUnit::activate(unsigned n)
                        units[i].index = i;
        }
 
-       if(cur_unit!=&units[n] && (cur_unit || n))
-               glActiveTexture(GL_TEXTURE0+n);
-       cur_unit = &units[n];
-
        return units[n];
 }
 
 TexUnit &TexUnit::current()
 {
        if(!cur_unit)
-               return activate(0);
+               get_unit(0).bind();
        return *cur_unit;
 }
 

diff --git a/source/texunit.h b/source/texunit.h
index 93f6dd085e80497450aae252c9dda4618211eccd..8bcb5f023059cf9ef3ea76e61e3a2a976da5fc8d 100644 (file)
--- a/source/texunit.h
+++ b/source/texunit.h
@@ -31,9 +31,10 @@ public:
        const TexEnv *get_texenv() const { return texenv; }
        bool set_texgen(unsigned, const TexGen *);
        const TexGen *get_texgen(unsigned);
+       void bind();
 
        static unsigned get_n_units();
-       static TexUnit &activate(unsigned);
+       static TexUnit &get_unit(unsigned);
        static TexUnit &current();
 };