Alpha = _pixels[i%16 * 64 + i]
Red = _pixels[i%16 * 64 + 16 + i]
Green = _pixels[i%16 * 64 + 32 + i]
Blue = _pixels[i%16 * 64 + 48 + i]

#ifndef LIBWIISPRITE_DRAWABLEIMAGE
#define LIBWIISPRITE_DRAWABLEIMAGE
 
#include

 namespace wsp{ //The namespace used in libwiisprite

  class DrawableImage : public Image{

      public:

	DrawableImage(); //Constructor
	virtual ~DrawableImage(); //Destructor

     u8 GetRed(u32 i);//Retrieve the red value of a designated pixel on the DrawableImage
     u8 GetGreen(u32 i);//Retrieve the blue value of a designated pixel on the DrawableImage
     u8 GetBlue(u32 i);//Retrieve the green value of a designated pixel on the DrawableImage
     u8 GetAlpha(u32 i);//Retrieve the alpha value of a designated pixel on the DrawableImage

     void SetRed(u32 i, u8 r);//Sets the red value of a designated pixel on the DrawableImage
     void SetGreen(u32 i, u8 g);//Sets the blue value of a designated pixel on the DrawableImage
     void SetBlue(u32 i, u8 b);//Sets the green value of a designated pixel on the DrawableImage
     void SetAlpha(u32 i, u8 a);//Sets the alpha value of a designated pixel on the DrawableImage

     bool CheckPixel(u32 i, u8 r, u8 g, u8 b, u8 a);/*Compares the designated pixel on the DrawableImage with the values given to call the function*/

     void SetPixel(u32 i, u8 r, u8 g, u8 b, u8 a);//Sets the color values of the designated pixel on the DrawableImage

     void MakeTransparent(u8 r, u8 g, u8 b, u8 a);//Makes all pixels that match those values in the DrawableImage transparent

    private:

    /*u8 * _pixels;
	u32 _width, _height;
	bool _initialized;
	GXTexObj _texObj;*/

  };
 };


 #endif

include
#include "drawableimage.h"
#include 
#include 
#include 

 using namespace wsp; //Libwiisprite namespace

  DrawableImage::DrawableImage(){
  }

  DrawableImage::~DrawableImage(){

    DestroyImage();
  }

  u8 DrawableImage::GetRed(u32 i){
  
   u8 Red;
  
   Red = _pixels;
  
   return Red;
  }

  u8 DrawableImage::GetGreen(u32 i){
  
   u8 Green;

   Green = _pixels[i+1];
  
   return Green;
  }

  u8 DrawableImage::GetBlue(u32 i){
  
   u8 Blue;

   Blue = _pixels[i+2];
  
   return Blue;
  }

  u8 DrawableImage::GetAlpha(u32 i){
  
   u8 Alpha;

   Alpha = _pixels[i+3];
  
   return Alpha;
  }

  void DrawableImage::SetRed(u32 i, u8 r){

   _pixels = r;

  }

  void DrawableImage::SetGreen(u32 i, u8 g){

  _pixels[i+1] = g;

  }

  void DrawableImage::SetBlue(u32 i, u8 b){

   _pixels[i+2] = b;

  }

  void DrawableImage::SetAlpha(u32 i, u8 a){
  
  _pixels[i+3] = a;
   
  }

  bool DrawableImage::CheckPixel(u32 i, u8 r, u8 g, u8 b, u8 a){

   if(GetRed(i) == r && GetGreen(i) == g && GetBlue(i) == b && GetAlpha(i) == a)
     return true;

    else
     return false;

  }

  void DrawableImage::SetPixel(u32 i, u8 r, u8 g, u8 b, u8 a){

     SetRed(i, r);
     SetGreen(i, g);
     SetBlue(i, b);
     SetAlpha(i, a);

   }

   void DrawableImage::MakeTransparent(u8 r, u8 g, u8 b, u8 a){

    u32 height = GetHeight();
    u32 width = GetWidth();
	u32 total = width*height;
	
	_InitializeImage(width, height);

     for(u32 i = 0; i <= total; i++){

        if(CheckPixel(i, r, g, b, a))
         SetPixel(i, 0, 0, 0, 0);

      }
     
    }

#include 
#include 
#include 
#include 
#include 
#include  // The main libwiisprite header.

#include "drawableimage.h"

using namespace wsp; //Libwiisprites namespace

int main(int argc, char **argv){

    int x = 320;
	int y = 240;
	int speed = 8;
	
	fatInitDefault();//Initialize the SanDisk
	
	// Create the game window and initalise the VIDEO subsystem
	GameWindow gwd;
	gwd.InitVideo();
	
	WPAD_Init(); //Initialize the Wiimote
	
	Image *image1 = new Image();
    image1->LoadImage("data/background.png");
	
	DrawableImage *image2 = new DrawableImage();
    image2->LoadImage("data/pointer.png");
	image2->MakeTransparent(0xFF, 255, 0, 255);//Check with ARGB
	
	
	Sprite *background = new Sprite();
	background->SetImage(image1);
	background->Draw();
	
	Sprite *bat = new Sprite();
	bat->SetImage(image2, 48, 48);

	for(;;)
	{
		WPAD_ScanPads();
		
		background->Draw();
		
		bat->SetPosition(x, y);
		bat->Draw();
		bat->NextFrame();
		
		if(WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_UP)
		x -= speed;
		
		if(WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_DOWN)
		x += speed;
		
		if(WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_RIGHT)
		y -= speed;
		
		if(WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_LEFT)
		y += speed;
		
		if((WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_UP) && (WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_RIGHT)){
		x -= speed/2;
		y -= speed/2;
		}
		
		if((WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_UP) && (WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_LEFT)){
		x -= speed/2;
		y += speed/2;
		}
		
		if((WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_DOWN) && (WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_RIGHT)){
		x += speed/2;
		y -= speed/2;
		}
		
		if((WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_DOWN) && (WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_LEFT)){
		x += speed/2;
		y += speed/2;
		}
		
		if(WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_A)//Leaving this in for additional trial
		image2->MakeTransparent(255, 0, 255, 0xFF);//Check with RGBA
		
		if(WPAD_ButtonsDown(WPAD_CHAN_0)&WPAD_BUTTON_HOME)
			break;
		
		if(y < 0)
		y = 0;
		
		if(y > 480)
		y = 480;
		
		if(x < 0)
		x = 0;
		
		if(x > 640)
		x = 640;
		
		gwd.Flush();
	}
	return 0;
}

Quote
chaosteil
Well, there may be one additional way you can achieve what you were looking for. Try to load the image, but into your own buffer. Use the libpng functions then to change the image data and then push the buffer to the Image class. This may work or may not work so much. I guess you should just try.