Convert-BMP-and-JPEG-images-to-a-bitmap


            Title: Convert BMP and JPEG images to a bitmap
Question: With Delphi it's easy to create a window and to load images.
But if you want use images for e.g. graphical effects
you need a bitmap to work with. But there is a problem.
JPGs do not have a Bitmap property.
Answer:
{
Insert images (BMPs or JPGs) to your window (tForm):
- click on image icon of the component Additional
- and insert it into your window
- double click it to load a BMP or JPG image file
- set the property 'visible' to false to hide it
- switch to the source code implementation
- call CopyImageToBitmap to create the needed bitmap
}
uses SysUtils, Windows, Graphics, ExtCtrls, JPEG;
:
:
//*********************************************************
// copy BMP or JPG image to given bitmap
//---------------------------------------------------------
procedure CopyImageToBitmap (im: tImage; bm: tBitmap);
begin
 if bm = nil
 then begin
 bm := tBitmap.Create;
 bm.PixelFormat := pfDevice;
 end;
 bm.Width := im.Picture.Width;
 bm.Height := im.Picture.Height;
 if im.Picture.Graphic is tJPEGImage
 then bm.Canvas.Draw (0,0, im.Picture.Graphic) // it's a JPG
 else bm.Canvas.Draw (0,0, im.Picture.Bitmap); // it's a BMP
end;
// example:
var texImage: tImage;
 tileBm: tBitmap;
:
:
 // image1 is the name of the inserted image
 texImage := image1; 
 tileBm := tBitmap.Create;
 tileBm.PixelFormat := pfDevice;
 CopyImageToBitmap (texImage, tileBm);
:
:
Graphic Delphi
