Support for anisotropic texture filtering

diff --git a/source/ext_texture_filter_anisotropic.cpp b/source/ext_texture_filter_anisotropic.cpp
new file mode 100644 (file)
index 0000000..e93249b
--- /dev/null
+++ b/source/ext_texture_filter_anisotropic.cpp
@@ -0,0 +1,18 @@
+#include "ext_texture_filter_anisotropic.h"
+
+namespace Msp {
+namespace GL {
+
+Extension::SupportLevel init_ext_texture_filter_anisotropic()
+{
+       if(is_supported("GL_EXT_texture_filter_anisotropic"))
+       {
+               return Extension::EXTENSION;
+       }
+       return Extension::UNSUPPORTED;
+}
+
+Extension EXT_texture_filter_anisotropic("GL_EXT_texture_filter_anisotropic", init_ext_texture_filter_anisotropic);
+
+} // namespace GL
+} // namespace Msp

diff --git a/source/ext_texture_filter_anisotropic.h b/source/ext_texture_filter_anisotropic.h
new file mode 100644 (file)
index 0000000..be7f5b1
--- /dev/null
+++ b/source/ext_texture_filter_anisotropic.h
@@ -0,0 +1,16 @@
+#ifndef MSP_GL_EXT_TEXTURE_FILTER_ANISOTROPIC_
+#define MSP_GL_EXT_TEXTURE_FILTER_ANISOTROPIC_
+
+#include "extension.h"
+#include "gl.h"
+#include <GL/glext.h>
+
+namespace Msp {
+namespace GL {
+
+extern Extension EXT_texture_filter_anisotropic;
+
+} // namespace GL
+} // namespace Msp
+
+#endif

diff --git a/source/texture.cpp b/source/texture.cpp
index c8a1371c5b0a7724effdeb33ec7f529e70372a47..e4d4ebf2ce138c6d716d9bdf9e497d3976c3e029 100644 (file)
--- a/source/texture.cpp
+++ b/source/texture.cpp
@@ -1,5 +1,6 @@
 #include <msp/strings/format.h>
 #include "error.h"
+#include "ext_texture_filter_anisotropic.h"
 #include "sgis_generate_mipmap.h"
 #include "texture.h"
 #include "texunit.h"
@@ -69,6 +70,8 @@ void Texture::update_parameter(int mask) const
                        glTexParameteri(target, GL_TEXTURE_MIN_FILTER, min_filter);
                if(mask&MAG_FILTER)
                        glTexParameteri(target, GL_TEXTURE_MAG_FILTER, mag_filter);
+               if(mask&MAX_ANISOTROPY)
+                       glTexParameteri(target, GL_TEXTURE_MAX_ANISOTROPY_EXT, max_anisotropy);
                if(mask&WRAP_S)
                        glTexParameteri(target, GL_TEXTURE_WRAP_S, wrap_s);
                if(mask&WRAP_T)
@@ -98,6 +101,16 @@ void Texture::set_mag_filter(TextureFilter f)
        update_parameter(MAG_FILTER);
 }
 
+void Texture::set_max_anisotropy(float a)
+{
+       if(a<1.0f)
+               throw invalid_argument("Texture::set_max_anisotropy");
+       else if(a>1.0f)
+               static Require _req(EXT_texture_filter_anisotropic);
+       max_anisotropy = a;
+       update_parameter(MAX_ANISOTROPY);
+}
+
 void Texture::set_wrap(TextureWrap w)
 {
        set_wrap_s(w);
@@ -196,6 +209,7 @@ void Texture::unbind_from(unsigned i)
 Texture::Loader::Loader(Texture &t):
        DataFile::ObjectLoader<Texture>(t)
 {
+       add("max_anisotropy", &Loader::max_anisotropy);
        add("generate_mipmap", &Loader::generate_mipmap);
        add("mag_filter", &Loader::mag_filter);
        add("min_filter", &Loader::min_filter);
@@ -215,6 +229,11 @@ void Texture::Loader::mag_filter(TextureFilter f)
        obj.set_mag_filter(f);
 }
 
+void Texture::Loader::max_anisotropy(float a)
+{
+       obj.set_max_anisotropy(a);
+}
+
 void Texture::Loader::min_filter(TextureFilter f)
 {
        obj.set_min_filter(f);

diff --git a/source/texture.h b/source/texture.h
index 30ad484cbc29835108788add581d54ad48791fd1..af0844c55e26938f00b2201e2f10abd576ece537 100644 (file)
--- a/source/texture.h
+++ b/source/texture.h
@@ -70,8 +70,10 @@ protected:
        {
        public:
                Loader(Texture &);
+       private:
                void generate_mipmap(bool);
                void mag_filter(TextureFilter);
+               void max_anisotropy(float);
                void min_filter(TextureFilter);
                void wrap(TextureWrap);
                void wrap_r(TextureWrap);
@@ -88,13 +90,15 @@ protected:
                WRAP_R = 16,
                GENERATE_MIPMAP = 32,
                COMPARE = 64,
-               COMPARE_FUNC = 128
+               COMPARE_FUNC = 128,
+               MAX_ANISOTROPY = 256
        };
 
        unsigned id;
        GLenum target;
        TextureFilter min_filter;
        TextureFilter mag_filter;
+       float max_anisotropy;
        TextureWrap wrap_s;
        TextureWrap wrap_t;
        TextureWrap wrap_r;
@@ -114,6 +118,7 @@ protected:
 public:
        void set_min_filter(TextureFilter);
        void set_mag_filter(TextureFilter);
+       void set_max_anisotropy(float);
 
        /** Sets the wrapping mode for all coordinates. */
        void set_wrap(TextureWrap);