Merge branch 'experimental' of /data/git-repository/acgl/libraries/acgl into experimental

include/ACGL/OpenGL/Tools.hh

@@ -18,6 +18,10 @@
 namespace ACGL{
 namespace OpenGL{
 
+//! queries some limits of the runtime which are used in ACGL internally. Client apps should not rely on these values, they are subject to changes. Gets called by ACGL::init()
+void initRuntimeDependentLimits();
+extern GLfloat ACGL_MAX_TEXTURE_MAX_ANISOTROPY;
+
 //! returns the size in bytes of the common gl types named by there GLenums.
 inline GLint getGLTypeSize ( GLenum _type )
 {

src/ACGL/ACGL.cc

@@ -59,6 +59,9 @@ bool init(void)
        return false;
     }
 
+    // gets runtime limits to be used internally:
+    OpenGL::initRuntimeDependentLimits();
+
     //
     // Register file types for loading. This has to be done if the library is
     // linked statically, because otherwise, the static registration of the

src/ACGL/OpenGL/Objects/Sampler.cc

@@ -31,10 +31,8 @@ void Sampler::setMaxAnisotropy( GLfloat _sampleCount )
 {
     if ( ACGL_EXT_texture_filter_anisotrophic() ) {
 		// anisotrophic filtering is supported:
-        GLfloat maxAnisotropicSamples;
-        glGetFloatv( GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &maxAnisotropicSamples );
-        _sampleCount = std::max( 1.0f, _sampleCount );
-        _sampleCount = std::min( maxAnisotropicSamples, _sampleCount );
+        _sampleCount = std::max( _sampleCount, 1.0f );
+        _sampleCount = std::min( _sampleCount, ACGL_MAX_TEXTURE_MAX_ANISOTROPY );
         glSamplerParameterf( mObjectName, GL_TEXTURE_MAX_ANISOTROPY_EXT, _sampleCount );
         openGLRareError();
     } else

src/ACGL/OpenGL/Objects/Texture.cc

@@ -60,10 +60,8 @@ void Texture::setAnisotropicFilter( GLfloat _sampleCount )
 {
     if ( ACGL_EXT_texture_filter_anisotrophic() ) {
 		// anisotrophic filtering is supported:
-        GLfloat maxAnisotropicSamples;
-        glGetFloatv( GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &maxAnisotropicSamples );
-        _sampleCount = std::max( 1.0f, _sampleCount );
-        _sampleCount = std::min( maxAnisotropicSamples, _sampleCount );
+        _sampleCount = std::max( _sampleCount, 1.0f );
+        _sampleCount = std::min( _sampleCount, ACGL_MAX_TEXTURE_MAX_ANISOTROPY );
         glBindTexture( mTarget, mObjectName );
         glTexParameterf( mTarget, GL_TEXTURE_MAX_ANISOTROPY_EXT, _sampleCount );
         openGLRareError();

src/ACGL/OpenGL/Tools.cc

@@ -12,6 +12,16 @@
 namespace ACGL{
 namespace OpenGL{
 
+GLfloat ACGL_MAX_TEXTURE_MAX_ANISOTROPY = -1.0f;
+void initRuntimeDependentLimits()
+{
+    if ( ACGL_EXT_texture_filter_anisotrophic() ) {
+        glGetFloatv( GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &ACGL_MAX_TEXTURE_MAX_ANISOTROPY );
+    } else {
+        ACGL_MAX_TEXTURE_MAX_ANISOTROPY = 0.0f;
+    }
+}
+
 //
 // This is a "private" function that should not be called from outside of this file.
 //