Texture / texture binding abstraction

Makefile

@@ -10,7 +10,8 @@ IMGUI = imgui.o imgui_demo.o imgui_draw.o
 DEMO = \
 	 main.o \
 	 imgui_impl_sdl.o \
-	 utilities.o
+	 utilities.o \
+	 texture.o
 
 DEMO_DEPS = $(DEMO:%.o=.%.d)
 

main.cc

@@ -2,6 +2,7 @@
 
 #include "imgui_impl_sdl.h"
 #include "utilities.hh"
+#include "texture.hh"
 
 
 /*= T_Main ===================================================================*/
@@ -59,6 +60,8 @@ T_Main::T_Main( )
 	ImGui_ImplSdl_Init( window );
 
 	initProgram( );
+
+	//T_Texture textureTest( 512 , 512 , E_TexType::R8 );
 }
 
 void T_Main::mainLoop( )

texture.cc

@@ -0,0 +1,94 @@
+#include "externals.hh"
+#include "texture.hh"
+
+
+T_Texture::T_Texture(
+		__rd__ const uint32_t width ,
+		__rd__ const uint32_t height ,
+		__rd__ const E_TexType type ,
+		__rd__ const uint32_t levels )
+	: width_( width ) , height_( height )
+{
+	assert( levels > 0 );
+
+	glGenTextures( 1 , &id_ );
+	glBindTexture( GL_TEXTURE_2D , id_ );
+
+	GLenum ifmt , fmt , dt;
+	switch ( type ) {
+		case E_TexType::RGBA8:
+			ifmt = GL_RGBA8;
+			fmt = GL_RGBA;
+			dt = GL_UNSIGNED_BYTE;
+			break;
+
+		case E_TexType::RGBA16F:
+			ifmt = GL_RGBA16F;
+			fmt = GL_RGBA;
+			dt = GL_FLOAT;
+			break;
+
+		case E_TexType::R8:
+			ifmt = GL_R8;
+			fmt = GL_RED;
+			dt = GL_UNSIGNED_BYTE;
+			break;
+
+		case E_TexType::R16F:
+			ifmt = GL_R16F;
+			fmt = GL_RED;
+			dt = GL_FLOAT;
+			break;
+	}
+
+	glTexParameteri( GL_TEXTURE_2D , GL_TEXTURE_MIN_LOD , 0 );
+	glTexParameteri( GL_TEXTURE_2D , GL_TEXTURE_MAX_LOD , levels - 1 );
+
+	uint32_t w = width , h = height;
+	for ( auto i = 0u ; i < levels ; i ++ ) {
+		glTexImage2D( GL_TEXTURE_2D , i , ifmt , w , h , 0 , fmt , dt , nullptr );
+		w >>= 2;
+		h >>= 2;
+		assert( w && h );
+	}
+
+	assert( glGetError( ) == GL_NO_ERROR );
+
+	glBindTexture( GL_TEXTURE_2D , 0 );
+}
+
+T_Texture::~T_Texture( )
+{
+	glDeleteTextures( 1 , &id_ );
+}
+
+
+/*============================================================================*/
+
+
+T_TextureBinding::T_TextureBinding(
+		__rd__ const uint32_t binding )
+	: binding_( binding ) , uniform_( 0 ) , texture_( nullptr )
+{ }
+
+void T_TextureBinding::clear( )
+{
+	uniform_ = 0;
+	texture_ = nullptr;
+}
+
+void T_TextureBinding::set(
+		__rd__ const uint32_t uniform ,
+		__rd__ T_Texture const& texture )
+{
+	uniform_ = uniform;
+	texture_ = &texture;
+}
+
+void T_TextureBinding::bind( ) const
+{
+	glActiveTexture( GL_TEXTURE0 + binding_ );
+	glBindTexture( GL_TEXTURE_2D , texture_ ? texture_->id( ) : 0 );
+	glUniform1i( uniform_ , binding_ );
+	assert( glGetError( ) == GL_NO_ERROR );
+}

texture.hh

@@ -0,0 +1,56 @@
+#pragma once
+#ifndef REAL_BUILD
+# include "externals.hh"
+#endif
+
+
+enum class E_TexType
+{
+	RGBA8 ,
+	RGBA16F ,
+	R8 ,
+	R16F ,
+};
+
+struct T_Texture
+{
+	T_Texture( ) = delete;
+	T_Texture( T_Texture const& ) = delete;
+	T_Texture( T_Texture&& ) = delete;
+
+	T_Texture(
+			__rd__ const uint32_t width ,
+			__rd__ const uint32_t height ,
+			__rd__ const E_TexType type ,
+			__rd__ const uint32_t levels = 1 );
+	~T_Texture( );
+
+	GLuint id( ) const noexcept { return id_; }
+	uint32_t width( ) const noexcept { return width_; }
+	uint32_t height( ) const noexcept { return height_; }
+
+    private:
+	GLuint id_;
+	uint32_t width_ , height_;
+};
+
+struct T_TextureBinding
+{
+	T_TextureBinding( ) = delete;
+	T_TextureBinding( T_TextureBinding const& ) = delete;
+	T_TextureBinding( T_TextureBinding&& ) = delete;
+
+	explicit T_TextureBinding(
+			__rd__ const uint32_t binding );
+
+	void clear( );
+	void set( __rd__ const uint32_t uniform ,
+			__rd__ T_Texture const& texture );
+
+	void bind( ) const;
+
+    private:
+	const uint32_t binding_;
+	uint32_t uniform_;
+	T_Texture const* texture_;
+};