glsandbox/Texture2D.cpp at master · dfighter1985/glsandbox · GitHub

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#ifndef GLEW_STATIC
#define GLEW_STATIC
#endif
#include <gl/glew.h>
#include <gl/gl.h>
#include <cassert>
#include "Texture2D.h"

void Texture2D::bind( unsigned int unit )
{
	glActiveTexture( GL_TEXTURE0 + unit );
	glBindTexture( GL_TEXTURE_2D, getId() );
}

void Texture2D::loadImage( Image &image )
{
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT );
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT );

	glPixelStorei( GL_UNPACK_ALIGNMENT, 1 );

	unsigned char depth = image.getDepth() / 8;
	unsigned short format;
	unsigned short components;

	switch( depth )
	{
	case 1:
		format = GL_LUMINANCE;
		components = GL_LUMINANCE;
		break;

	case 3:
		format = GL_BGR;
		components = GL_RGB;
		break;

	case 4:
		format = GL_BGRA;
		components = GL_RGBA;
		break;

	default:
		assert( false );
		break;
	}

	glTexImage2D( GL_TEXTURE_2D,
				0,
				components,
				image.getWidth(),
				image.getHeight(),
				0,
				format,
				GL_UNSIGNED_BYTE,
				image.getBuffer() );

}