Always bind textures in a specific texture unit

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

diff --git a/source/texunit.cpp b/source/texunit.cpp
index d581598a6c190e2caf46c59d11140d403c30e79b..982e524e0189fa74a10181c9a2ff7f7014e8746e 100644 (file)
--- a/source/texunit.cpp
+++ b/source/texunit.cpp
@@ -1,8 +1,8 @@
 #include <stdexcept>
-#include "extension.h"
+#include <msp/gl/extensions/arb_multitexture.h>
+#include <msp/gl/extensions/arb_vertex_shader.h>
 #include "gl.h"
 #include "texunit.h"
-#include "version_1_3.h"
 
 using namespace std;
 
@@ -36,7 +36,7 @@ bool TexUnit::set_texenv(const TexEnv *env)
 bool TexUnit::set_texgen(unsigned i, const TexGen *gen)
 {
        if(i>=4)
-               throw invalid_argument("TexUnit::set_texgen");
+               throw out_of_range("TexUnit::set_texgen");
        bool result = (texgen[i]!=gen);
        texgen[i] = gen;
        return result;
@@ -45,18 +45,25 @@ bool TexUnit::set_texgen(unsigned i, const TexGen *gen)
 const TexGen *TexUnit::get_texgen(unsigned i)
 {
        if(i>=4)
-               throw invalid_argument("TexUnit::get_texgen");
+               throw out_of_range("TexUnit::get_texgen");
        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;
        if(count<0)
        {
-               if(is_version_at_least(2, 0) || is_supported("ARB_vertex_shader"))
+               if(ARB_vertex_shader)
                        glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, &count);
-               else if(is_version_at_least(1, 3))
+               else if(ARB_multitexture)
                        glGetIntegerv(GL_MAX_TEXTURE_UNITS, &count);
                else
                        count = 1;
@@ -64,17 +71,20 @@ 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)
+       {
+               unsigned i = units.size();
                units.resize(n+1);
-
-       if(cur_unit!=&units[n] && (cur_unit || n))
-               glActiveTexture(GL_TEXTURE0+n);
-       cur_unit = &units[n];
+               for(; i<units.size(); ++i)
+                       units[i].index = i;
+       }
 
        return units[n];
 }
@@ -82,7 +92,7 @@ TexUnit &TexUnit::activate(unsigned n)
 TexUnit &TexUnit::current()
 {
        if(!cur_unit)
-               return activate(0);
+               get_unit(0).bind();
        return *cur_unit;
 }