GDI+ Bitmaps

[jgeorge21]

In my quest for a simple to use image loading library I came across GDI+. I only want to use the portion of GDI+ that loads images, since it loads every image type that I would ever need into a DIB (which I can extract and feed OpenGL). However, I have the most annoying and frustrating issue: the image is not loaded and the lastResult member of the Bitmap object indicates InvalidParameter. Obviously I'm feeding it something bad. The relevant code snippet follows: xBoolean xImage::Load (char *fileName, xBoolean mipmap) { BitmapData *bmpData = new BitmapData (); Rect *rect = new Rect (); sint32 format, stride; uint32 i, j; xbyte *tempBuffer; uint32 wideLen; WCHAR *fileNameW = NULL; if (fileName == NULL) // Early out if string is NULL return xfalse; // Convert C string to UNICODE wideLen = MultiByteToWideChar (CP_ACP, MB_PRECOMPOSED, fileName, -1, NULL, 0); // Get necessary length fileNameW = (WCHAR *)malloc (wideLen); // Alloc string MultiByteToWideChar (CP_ACP, MB_PRECOMPOSED, fileName, -1, fileNameW, wideLen); // Translate string Bitmap bmp ((const WCHAR *)fileNameW, FALSE); ... The string fileName is being properly translated to fileNameW as below: // Original String fileName[0] 119 'w' char fileName[1] 104 'h' char fileName[2] 105 'i' char fileName[3] 116 't' char fileName[4] 101 'e' char fileName[5] 46 '.' char fileName[6] 116 't' char fileName[7] 103 'g' char fileName[8] 97 'a' char fileName[9] 0 char // Wide String fileNameW[0] 119 unsigned short fileNameW[1] 104 unsigned short fileNameW[2] 105 unsigned short fileNameW[3] 116 unsigned short fileNameW[4] 101 unsigned short fileNameW[5] 46 unsigned short fileNameW[6] 116 unsigned short fileNameW[7] 103 unsigned short fileNameW[8] 97 unsigned short fileNameW[9] 0 unsigned short The constructor for the Bitmap object is as follows: class Bitmap : public Image { public: friend class Image; friend class CachedBitmap; Bitmap( IN const WCHAR *filename, IN BOOL useEmbeddedColorManagement = FALSE ); Recall that the lastResult member is being set to InvalidParameter. Here are the possible GDI+ return values: enum Status { Ok = 0, GenericError = 1, InvalidParameter = 2, OutOfMemory = 3, ObjectBusy = 4, InsufficientBuffer = 5, NotImplemented = 6, Win32Error = 7, WrongState = 8, Aborted = 9, FileNotF

[PJ Arends]

jgeorge21 wrote: fileName[5] 46 '.' char fileName[6] 116 't' char fileName[7] 103 'g' char fileName[8] 97 'a' char From MSDN: [quote] Bitmap::Bitmap(filename, useIcm) Creates a Bitmap object based on an image file. Bitmap( const WCHAR* filename, BOOL useIcm ); Parameters filename [in] Pointer to a null-terminated string that specifies the path name of the image file. The graphics file formats supported by GDI+ are BMP, GIF, JPEG, PNG, TIFF, Exif, WMF, and EMF. [/quote] I do not see tga in the list of supported formats. Try http://www.codeproject.com/bitmap/cximage.asp[^] instead.

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