02-08-2020, 01:45 AM
(This post was last modified: 02-08-2020, 01:45 AM by Alexandre Machado.)
Bitmaps in Delphi are not thread safe. If you create/manipulate Bitmaps at runtime you can eventually find a problem. IW has some special code to handle it and avoid this problem but still, if your code is dealing directly with bitmaps you need to lock the canvas before manipulating it and unlock the bitmap canvas after doing it. I'm not exactly sure how you are dealing with it and Soren provided very few details. So It is impossible to tell more.
Regarding your report:
Browsers don't know bitmaps. Bitmap is mostly a Windows thing (although Linux and others can also handle it). Browsers know PNG, JPG, GIF among other graphic types. If you are using BMP you are forcing IW to convert them at run time to any other of the known extensions.
PreProcessImage should work as long as you are setting the bitmap using TIWImage.Picture property. If you are doing anything other than that it won't work for you. It is an optimization option which is supposed to work with regular use of TIWImage, not to handle every possible use case (including changing the bitmap directly)
Regarding your report:
Browsers don't know bitmaps. Bitmap is mostly a Windows thing (although Linux and others can also handle it). Browsers know PNG, JPG, GIF among other graphic types. If you are using BMP you are forcing IW to convert them at run time to any other of the known extensions.
PreProcessImage should work as long as you are setting the bitmap using TIWImage.Picture property. If you are doing anything other than that it won't work for you. It is an optimization option which is supposed to work with regular use of TIWImage, not to handle every possible use case (including changing the bitmap directly)