Hi, I've just started messing with DirectX programming. I'm learning from a not-so-great book...heh. I'm starting with a 2D game. Anyway, I have this bizarre problem where my transparent color stopped working for no apparent reason. It worked two nights ago, then I merely added code that reads the game's map from a file. (before I just used a non-pointer array as a test case) I haven't changed the code below, which to my knowledge is the only important code when it comes to transparency. I load all bitmaps with the following:

IDirect3DSurface9* getSurfaceFromBitmap(std::string filename, int width, int height)
{
	HRESULT hResult;
	IDirect3DSurface9* surface = NULL;

	// verify that the image exists...the hard way.
	D3DXIMAGE_INFO imageInfo;
	hResult = D3DXGetImageInfoFromFile(filename.c_str(), &imageInfo);
	if (FAILED(hResult))
		return NULL;

	hResult = pd3dDevice->CreateOffscreenPlainSurface(width, height, D3DFMT_A8R8G8B8, D3DPOOL_DEFAULT, &surface, NULL);
	if (FAILED(hResult))
		return NULL;

	hResult = D3DXLoadSurfaceFromFile(surface, NULL, NULL, filename.c_str(), NULL, D3DX_DEFAULT, D3DCOLOR_XRGB(40, 0, 20), NULL);
	if (FAILED(hResult))
		return NULL;

	return surface;
}

Yesterday, the transparent color worked. Today, it turns black. So now sprites and tiles have the ugly "black box" effect. I tried setting the backbuffer to A8R8G8B8 instead of unknown, that didn't help either. Is there anything I'm missing? Was it just a fluke in DirectX's design that made it work fine before? One more question: Is there anywhere I can find a downloadable DirectX API listing?

Quote:Original post by matthughson
Have you tried taking out the code that reads the game's map from a file to check if that change is actually what broke it?

Quote:Is there anywhere I can find a downloadable DirectX API listing?

You mean like the help docs for the API? That is included with the SDK (or was the last time I downloaded it). I think it ussually gets added to your start menu with the rest of the SDK stuff (sample browser etc).

Matt

Ah, it's there. :) I didn't notice it because it's like a typical help manual...I'm used to the web-based API's like Sun's for Java.

I tried taking out the new code too...that didn't help at all. Is there anything else I need to do (besides the code I already posted) to make them properly transparent? I made sure that all the images do load with that code as well. I've also tested others' DirectX games to make sure it's not an issue with my system.

I tried (also) to use D3DCOLOR_ARGB() and a variety of alpha settings...no dice.

Ok, I tried making a test case exactly like the original one I thought worked, retracing my significant steps...it doesn't work. My transparent color turns black.

Here's the entire code for the test case...runs off one .cpp file. I added d3d9.lib and d3dx9.lib. I tested with a image with some red (255,0,0) in it. The red turns black, it doesn't become the background sky blue color. I looked through the API and it didn't help explain why this won't work. What could possibly be wrong with this code? Is it a global feature with DirectX I've forgotten to do?

#include <windows.h>#include <mmsystem.h>#include <d3d9.h>#include <d3dx9tex.h>#include <string>using namespace std;HINSTANCE hInst;				// holds the instance for this appHWND wndHandle;					// global window handleLPDIRECT3D9             pD3D;LPDIRECT3DDEVICE9       pd3dDevice;////////////////////////////////////////////// forward declarationsbool    initWindow(HINSTANCE hInstance);LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);IDirect3DSurface9* character;// direct3D functionsHRESULT SetupVB();bool initDirect3D(HWND hwnd);void shutdown(void);void render();IDirect3DSurface9* getSurfaceFromBitmap(std::string filename, int length, int width);IDirect3DSurface9* getSurfaceFromBitmap(std::string filename, int height, int width){	HRESULT hResult;	IDirect3DSurface9* surface = NULL;	D3DXIMAGE_INFO imageInfo;	hResult = D3DXGetImageInfoFromFile(filename.c_str(), &imageInfo);	if FAILED(hResult)		return NULL;	hResult = pd3dDevice->CreateOffscreenPlainSurface(width, height,                       D3DFMT_A8R8G8B8, D3DPOOL_DEFAULT, &surface, NULL);	if FAILED(hResult)		return NULL;	hResult = D3DXLoadSurfaceFromFile(surface, NULL, NULL, filename.c_str(),                      NULL, D3DX_DEFAULT, D3DCOLOR_ARGB(0xff, 255, 0, 0), NULL);	if FAILED(hResult)		return NULL;	return surface;}int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow){	// call our function to init and create our window	if (!initWindow(hInstance))	{		MessageBox(NULL, "Unable to create window", "ERROR", MB_OK);		return false;	}	// init direct3d	initDirect3D(wndHandle);	// setup the vertex buffer and add the triangle to it.	SetupVB();	character = getSurfaceFromBitmap("./char.bmp", 720, 192);	// Main message loop:	// Enter the message loop    MSG msg;     ZeroMemory( &msg, sizeof(msg) );    while( msg.message!=WM_QUIT )    {		// check for messages		if( PeekMessage( &msg, NULL, 0U, 0U, PM_REMOVE ) )        {			TranslateMessage( &msg );            DispatchMessage( &msg );        }		// this is called when no messages are pending		else		{			// call our render function			pd3dDevice->Clear( 0, NULL, D3DCLEAR_TARGET,                                  D3DCOLOR_XRGB(0,255,255), 1.0f, 0 );			pd3dDevice->BeginScene();			// render			render();						pd3dDevice->EndScene();			pd3dDevice->Present( NULL, NULL, NULL, NULL );			}    }	// shutdown the directx manager	shutdown();	return (int) msg.wParam;}HRESULT SetupVB(){    return S_OK;}bool initDirect3D(HWND hwnd){	HRESULT hr;	if( NULL == ( pD3D = Direct3DCreate9( D3D_SDK_VERSION ) ) )	{		return false;	}	D3DPRESENT_PARAMETERS d3dpp;     ZeroMemory( &d3dpp, sizeof(d3dpp) );    d3dpp.Windowed = TRUE;    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;    d3dpp.BackBufferFormat = D3DFMT_UNKNOWN;	d3dpp.BackBufferCount  = 1;	d3dpp.BackBufferHeight = 480;	d3dpp.BackBufferWidth  = 640;	d3dpp.hDeviceWindow    = hwnd;    hr = pD3D->CreateDevice( D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hwnd,                             D3DCREATE_SOFTWARE_VERTEXPROCESSING,                             &d3dpp, &pd3dDevice );	if FAILED (hr)    {        return false;    }	return true;}void render(){	//pd3dDevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 255, 255), 1.0f, 0);	RECT dest;	RECT src;	src.top = 0; src.left = 0; src.bottom = 72; src.right = 48;	dest.top = 0; dest.left = 0; dest.bottom = 72; dest.right = 48;	IDirect3DSurface9* backbuffer = NULL;	pd3dDevice->GetBackBuffer(0, 0, D3DBACKBUFFER_TYPE_MONO, &backbuffer);	pd3dDevice->StretchRect(character, &src, backbuffer, &dest, D3DTEXF_NONE);}void shutdown(void){    if( pd3dDevice != NULL) 	{        pd3dDevice->Release();		pd3dDevice = NULL;	}    if( pD3D != NULL)	{        pD3D->Release();		pD3D = NULL;	}}bool initWindow(HINSTANCE hInstance){	WNDCLASSEX wcex;	wcex.cbSize = sizeof(WNDCLASSEX);	wcex.style			= CS_HREDRAW | CS_VREDRAW;	wcex.lpfnWndProc	= (WNDPROC)WndProc;	wcex.cbClsExtra		= 0;	wcex.cbWndExtra		= 0;	wcex.hInstance		= hInstance;	wcex.hIcon			= 0;	wcex.hCursor		= LoadCursor(NULL, IDC_ARROW);	wcex.hbrBackground	= (HBRUSH)(COLOR_WINDOW+1);	wcex.lpszMenuName	= NULL;	wcex.lpszClassName	= "DirectXExample";	wcex.hIconSm		= 0;	RegisterClassEx(&wcex);	wndHandle = CreateWindow("DirectXExample", 							 "DirectXExample", 							 WS_OVERLAPPEDWINDOW,							 CW_USEDEFAULT, 							 CW_USEDEFAULT, 							 640, 							 480, 							 NULL, 							 NULL, 							 hInstance, 							 NULL);   if (!wndHandle)      return false;      ShowWindow(wndHandle, SW_SHOW);   UpdateWindow(wndHandle);   return true;}LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam){	switch (message) 	{		case WM_DESTROY:			PostQuitMessage(0);			break;	}	return DefWindowProc(hWnd, message, wParam, lParam);}