Complete rewrite of extension handling

[libs/gl.git] / source / texunit.cpp

diff --git a/source/texunit.cpp b/source/texunit.cpp
index bda7599143a11bf05abcf330a58eca6895c3da67..b19e791727c0e9f6d006c7a51eb58d3b0d634ed2 100644 (file)
--- a/source/texunit.cpp
+++ b/source/texunit.cpp
@@ -1,40 +1,82 @@
-/* $Id$
-
-This file is part of libmspgl
-Copyright © 2007  Mikko Rasa, Mikkosoft Productions
-Distributed under the LGPL
-*/
-
-#include "extension.h"
+#include <stdexcept>
+#include "arb_multitexture.h"
+#include "arb_vertex_shader.h"
 #include "gl.h"
 #include "texunit.h"
-#include "version_1_3.h"
 
 using namespace std;
 
 namespace Msp {
 namespace GL {
 
+vector<TexUnit> TexUnit::units;
+TexUnit *TexUnit::cur_unit = 0;
+
 TexUnit::TexUnit():
-       texture(0)
+       texture(0),
+       texenv(0)
 {
-       require_version(1, 3);
+       fill(texgen, texgen+4, static_cast<const TexGen *>(0));
 }
 
 bool TexUnit::set_texture(const Texture *tex)
 {
-       bool result=(tex!=texture);
-       texture=tex;
+       bool result = (tex!=texture);
+       texture = tex;
        return result;
 }
 
+bool TexUnit::set_texenv(const TexEnv *env)
+{
+       bool result = (texenv!=env);
+       texenv = env;
+       return result;
+}
+
+bool TexUnit::set_texgen(unsigned i, const TexGen *gen)
+{
+       if(i>=4)
+               throw invalid_argument("TexUnit::set_texgen");
+       bool result = (texgen[i]!=gen);
+       texgen[i] = gen;
+       return result;
+}
+
+const TexGen *TexUnit::get_texgen(unsigned i)
+{
+       if(i>=4)
+               throw invalid_argument("TexUnit::get_texgen");
+       return texgen[i];
+}
+
+unsigned TexUnit::get_n_units()
+{
+       static int count = -1;
+       if(count<0)
+       {
+               if(ARB_vertex_shader)
+                       glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, &count);
+               else if(ARB_multitexture)
+                       glGetIntegerv(GL_MAX_TEXTURE_UNITS, &count);
+               else
+                       count = 1;
+       }
+       return count;
+}
+
 TexUnit &TexUnit::activate(unsigned n)
 {
+       if(n>0)
+               static Require _req(ARB_multitexture);
+       if(n>=get_n_units())
+               throw out_of_range("TexUnit::activate");
+
        if(units.size()<=n)
                units.resize(n+1);
 
-       glActiveTexture(GL_TEXTURE0+n);
-       cur_unit=&units[n];
+       if(cur_unit!=&units[n] && (cur_unit || n))
+               glActiveTexture(GL_TEXTURE0+n);
+       cur_unit = &units[n];
 
        return units[n];
 }
@@ -46,8 +88,5 @@ TexUnit &TexUnit::current()
        return *cur_unit;
 }
 
-vector<TexUnit> TexUnit::units;
-TexUnit *TexUnit::cur_unit=0;
-
 } // namespace GL
 } // namespace Msp