* Add AllegroFlare/CubemapTextureBinder

Author: MarkOates

include/AllegroFlare/CubemapTextureBinder.hpp

@@ -0,0 +1,27 @@
+#pragma once
+
+
+#include <string>
+
+
+namespace AllegroFlare { class Cubemap; };
+
+
+namespace AllegroFlare
+{
+   class CubemapTextureBinder
+   {
+   private:
+      std::string name;
+      AllegroFlare::Cubemap *cubemap;
+      int unit;
+
+   public:
+      CubemapTextureBinder(std::string name="[unset-name]", AllegroFlare::Cubemap *cubemap=nullptr, int unit=0);
+      ~CubemapTextureBinder();
+
+      bool bind();
+   };
+}
+
+

include/AllegroFlare/Shader.hpp

@@ -4,7 +4,9 @@
 
 #include <allegro5/allegro.h>
 #include <AllegroFlare/Vec3D.hpp>
-#include <AllegroFlare/Cubemap.hpp>
+
+
+namespace AllegroFlare { class Cubemap; }
 
 
 

src/AllegroFlare/CubemapTextureBinder.cpp

@@ -0,0 +1,69 @@
+
+
+#define ALLEGRO_UNSTABLE
+
+#include <AllegroFlare/CubemapTextureBinder.hpp>
+
+#include <AllegroFlare/Cubemap.hpp>
+#include <iostream> // for cout, TODO: replace with AllegroFlare::Logger
+
+
+
+namespace AllegroFlare
+{
+
+
+CubemapTextureBinder::CubemapTextureBinder(std::string name, AllegroFlare::Cubemap *cubemap, int unit)
+   : name(name)
+   , cubemap(cubemap)
+   , unit(unit)
+{
+}
+
+
+CubemapTextureBinder::~CubemapTextureBinder()
+{
+}
+
+
+bool CubemapTextureBinder::bind()
+{
+   if (!cubemap) return false;
+   // grab the currently active shader program
+   GLint currProgram;
+   glGetIntegerv(GL_CURRENT_PROGRAM, &currProgram);
+   GLint shader_program_object = currProgram;
+
+   // get and verify that the uniform name is there and valid
+   GLint handle = glGetUniformLocation(shader_program_object, name.c_str());
+   if (handle < 0)
+   {
+      // this warning is silenced because there are instances where a user
+      // intentionally attempts to assign the uniform even knowing it is not there.
+      // a better reporting mechanisim might be used for all Shader::set_* functions.
+      //std::cout << "uniform not found for \"" << name << "\" in shader" << std::endl;
+      return false;
+   }
+
+   // bind it
+   glActiveTexture(GL_TEXTURE0 + unit);
+   glBindTexture(GL_TEXTURE_CUBE_MAP_EXT, cubemap->get_id());
+   glUniform1i(handle, unit);
+
+   // check for errors
+   GLenum err = glGetError();
+   if (err != 0)
+   {
+      // NOTE: in the internal Allegro 5 code, this pattern returns the acual message, rather
+      // than the error number.  However, the funciton to get the message for the error
+      // is an internal Allegro function.  This will work for now.
+      std::cout << "[Shader::set_sampler] error: glGetError() returned " << err << std::endl;
+      return err;
+   }
+   return true;
+}
+
+
+} // namespace AllegroFlare
+
+

src/AllegroFlare/Shader.cpp

@@ -9,6 +9,8 @@
 #include <sstream>
 
 #include <AllegroFlare/Logger.hpp>
+#include <AllegroFlare/Cubemap.hpp>
+
 
 
 namespace AllegroFlare

tests/AllegroFlare/CubemapTextureBinderTest.cpp

@@ -0,0 +1,18 @@
+
+#include <gtest/gtest.h>
+
+#include <AllegroFlare/CubemapTextureBinder.hpp>
+
+
+TEST(AllegroFlare_CubemapTextureBinderTest, can_be_created_without_blowing_up)
+{
+   AllegroFlare::CubemapTextureBinder cube_map_texture_binder;
+}
+
+
+TEST(AllegroFlare_CubemapTextureBinderTest, bind__will_bind_the_texture_to_the_shader_uniform)
+{
+   // TODO
+}
+
+