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How do I get D3DXLoadSurfaceFromFile to have trancparentcy?

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The issue is that my program draws a black box around the bmp when I want it not to draw anything that is solid green or 0,255,0. What do I need to add or change to get that to work?

     //get width and height from bitmap file
     D3DXIMAGE_INFO info;
     HRESULT result = D3DXGetImageInfoFromFile(filename.c_str(), &info);
     if (result != D3D_OK) return NULL;

     //create surface
     result = d3ddev->CreateOffscreenPlainSurface(
          info.Width,         //width of the surface
          info.Height,        //height of the surface
          D3DFMT_X8R8G8B8,    //surface format
          D3DPOOL_DEFAULT,    //memory pool to use
          &image,             //pointer to the surface
          NULL);              //reserved (always NULL)

      if (result != D3D_OK) return NULL;

      //load surface from file into newly created surface
      result = D3DXLoadSurfaceFromFile(
          image,                  //destination surface
          NULL,                   //destination palette
          NULL,                   //destination rectangle
          filename.c_str(),       //source filename
          NULL,                   //source rectangle
          D3DX_DEFAULT,           //controls how image is filtered
          D3DCOLOR_XRGB(0,255,0),   //for transparency (0 for none)
          NULL);                  //source image info (usually NULL)

      //make sure file was loaded okay
      if (result != D3D_OK) return NULL;

      return image;

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Try creating a D3DFMT_A8R8G8B8 image instead - you need an alpha channel to get transparency. Also make sure the alpha blending render states are set correctly when you draw it.

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Thanks I will try that as soon as I can get my program to compile.

the issue is

1>MyDirectX.obj : error LNK2001: unresolved external symbol "struct ID3DXSprite * spriteobj" (?spriteobj@@3PAUID3DXSprite@@A)
1>MyGame.obj : error LNK2001: unresolved external symbol "struct ID3DXSprite * spriteobj" (?spriteobj@@3PAUID3DXSprite@@A)

this is what I have

#pragma comment(lib,"d3dx9.lib")
#pragma comment(lib,"winmm.lib")
#pragma comment(lib,"user32.lib")
#pragma comment(lib,"gdi32.lib")
#pragma comment(lib,"dxguid.lib")
#pragma comment(lib,"d3dxof.lib")
#pragma comment(lib,"d3d9.lib")
#pragma comment(lib,"d3dx9d.lib")
#pragma comment(lib,"dinput8.lib")
#pragma comment(lib,"xinput.lib")

#include <d3dx9.h>
#include <windows.h>
#include <d3d9.h>
#include <dinput.h>
#include <xinput.h>
#include <ctime>
#include <iostream>
#include <iomanip>

I also have the folders set right becuase it was working tell I tryed adding LPD3DXSPRITE to the project and now for some reason its not finding the lib or I am starting it wrong

extern LPD3DXSPRITE spriteobj;

D3DXCreateSprite(d3ddev, &spriteobj);

D3DXVECTOR3 pos2( bomb.x, bomb.y, 0);
spriteobj->Draw( bomb_surf,NULL ,NULL, &pos2,

if (spriteobj) spriteobj->Release();

other then that I have no idea

I am using vc++ 2010
and windows 7 64bit

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You have:
extern LPD3DXSPRITE spriteobj;
Which tells the compiler that a LPD3DXSPRITE named spriteobj exists, but you don't declare it anywhere. You need to add this in one .cpp file at global scope:
LPD3DXSPRITE spriteobj = NULL;

Also, about the original problem: If you want alpha, you almost certainly want to use textures rather than surfaces, especially if you're using ID3DXSprite - in which case you should be using D3DXCreateTextureFromFileEx instead of D3DXLoadSurfaceFromFile.

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thanks that was what the issue was.

Its working now but its going way to fast and I am tring to figure a way to slow the images down.

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