Ian, can you try some 4-bit and 8-bit bmp images from other sources, and verify whether they can be displayed on upgraded iOS/Mac? I want to make sure if there are any bugs in bmp addon on pixel bmp.
On Mon, Oct 10, 2022 at 7:42 AM Ian Clark <[email protected]> wrote: > Thanks Bill. > > I've been able to use your updated graphics/bmp to alter j scripts *only* > in > j901-for-iOS as it currently resides on App Store, and fix viewmat. > Altering the jscripts is something the iPad owner can do, without the need > to update the app itself. > > Existing j901-for-iOS users who have upgraded to the latest iOS and iPadOS > will find the upgrade breaks viewmat. > Workaround: > > 1) Use pacman to update addon: graphics/bmp in a Mac running j904 > > 2) copy the folder: ~addons/graphics/bmp/ to your iCloud Drive (to make it > visible on your iPad) > > 3) On your iPad, launch j901 if it's not already launched. Go the Home view > if it is not already showing: ⌘T > > 4) Use the Files App to copy folder: bmp/ into: j901/j/addons/graphics/ > […replace] > > 5) In j901 Home view, enter > load 'graphics/bmp' > > 6) Edit or redefine existing viewmat_z_ to replace the line: > mat writebmp f > with: > mat writebmp f ; 24 > > An update to the App Store app is ready-to-go as soon as I've finished > testing it. Viewmat will work, and the above workaround won't be necessary. > > > On Sun, 9 Oct 2022 at 04:59, bill lam <[email protected]> wrote: > > > I have made a minor fix to bmp addon to fix DIB header size info. Please > > get the update from Pacman. > > Nevertheless mac still can not recognize the bmp file of your 2x2 sample > . > > The reason may be bmp addon trying to optimize the bmp file size using > > pixel table whenever possible by default. > > by forcing 24-bit non-pixel output, it produces a bmp that can be display > > on mac > > data writebmp 24;~ jpath 'some.bmp' > > > > My conclusion is that mac dropped support 4-bit bmp format, but you can > > workaround it by forcing bmp addon to use 24-bit bmp. > > > > > > > > On Tue, Oct 4, 2022 at 9:24 AM Ian Clark <[email protected]> wrote: > > > > > I don't know. I asked Apple on 22 Sep 2022 but they still haven't > > replied. > > > > > > Here's the code I've used to generate a BMP which *does* work on latest > > > iPadOS and macOS. > > > This is what I call: Apple-compliant. Strictly speaking it is > > > Wikipedia-compliant. > > > > > > NB.48 - generate sample bitmap / Apple TSI, Thu 22 Sep 2022 > > > > > > NB. https://en.wikipedia.org/wiki/BMP_file_format#Example_1 > > > > > > 0 :0 > > > > > > Fri 23 Sep 2022 03:15:45 > > > > > > - > > > > > > Produces very small bitmap. BUT Apple compliant. > > > > > > As it stands, 2835 px/m is 2.835 px/mm > > > > > > But increasing the print resolution (*16) no apparent difference. > > > > > > (But px/inch has gone down to 72) > > > > > > If substituted for j/slate/vmat1.bmp, 2x2 colors shown, but fuzzy > edges. > > > > > > ) > > > > > > cocurrent 'base' > > > > > > > > > hextable=: x4f 0 : 0 > > > > > > 42 4D "BM" ID field (42h, 4Dh) > > > > > > 46 00 00 00 70 bytes (54+16) Size of the BMP file (54 bytes header + 16 > > > bytes data) > > > > > > 00 00 Unused Application specific > > > > > > 00 00 Unused Application specific > > > > > > 36 00 00 00 54 bytes (14+40) Offset where the pixel array (bitmap data) > > can > > > be found > > > > > > DIB Header > > > > > > 28 00 00 00 40 bytes Number of bytes in the DIB header (from this > point) > > > > > > 02 00 00 00 2 pixels (left to right order) Width of the bitmap in > pixels > > > > > > 02 00 00 00 2 pixels (bottom to top order) Height of the bitmap in > > pixels. > > > Positive for bottom to top pixel order. > > > > > > 01 00 1 plane Number of color planes being used > > > > > > 18 00 24 bits Number of bits per pixel > > > > > > 00 00 00 00 0 BI_RGB, no pixel array compression used > > > > > > 10 00 00 00 16 bytes Size of the raw bitmap data (including padding) > > > > > > 13 0B 00 00 2835 pixels/metre horizontal Print resolution of the image, > > 72 > > > DPI × 39.3701 inches per metre yields 2834.6472 > > > > > > 13 0B 00 00 2835 pixels/metre vertical > > > > > > 00 00 00 00 0 colors Number of colors in the palette > > > > > > 00 00 00 00 0 important colors 0 means all colors are important > > > > > > Start of pixel array (bitmap data) > > > > > > 00 00 FF 0 0 255 Red, Pixel (0,1) > > > > > > FF FF FF 255 255 255 White, Pixel (1,1) > > > > > > 00 00 0 0 Padding for 4 byte alignment (could be a value other than > zero) > > > > > > FF 00 00 255 0 0 Blue, Pixel (0,0) > > > > > > 00 FF 00 0 255 0 Green, Pixel (1,0) > > > > > > 00 00 0 0 Padding for 4 byte alignment (could be a value other than > zero) > > > > > > ) > > > > > > > > > NB. reduce px/inch --> 1/16 [0B13]--> [00B1] > > > > > > NB. hextable=: x4f 0 : 0 > > > > > > NB. 42 4D "BM" ID field (42h, 4Dh) > > > > > > NB. 46 00 00 00 70 bytes (54+16) Size of the BMP file (54 bytes header > + > > 16 > > > bytes data) > > > > > > NB. 00 00 Unused Application specific > > > > > > NB. 00 00 Unused Application specific > > > > > > NB. 36 00 00 00 54 bytes (14+40) Offset where the pixel array (bitmap > > data) > > > can be found > > > > > > NB. DIB Header > > > > > > NB. 28 00 00 00 40 bytes Number of bytes in the DIB header (from this > > > point) > > > > > > NB. 02 00 00 00 2 pixels (left to right order) Width of the bitmap in > > > pixels > > > > > > NB. 02 00 00 00 2 pixels (bottom to top order) Height of the bitmap in > > > pixels. Positive for bottom to top pixel order. > > > > > > NB. 01 00 1 plane Number of color planes being used > > > > > > NB. 18 00 24 bits Number of bits per pixel > > > > > > NB. 00 00 00 00 0 BI_RGB, no pixel array compression used > > > > > > NB. 10 00 00 00 16 bytes Size of the raw bitmap data (including > padding) > > > > > > NB. 01 00 00 00 ?? pixels/metre horizontal Print resolution of the > image, > > > 72 DPI × 39.3701 inches per metre yields 2834.6472 > > > > > > NB. 01 00 00 00 ?? pixels/metre vertical > > > > > > NB. 00 00 00 00 0 colors Number of colors in the palette > > > > > > NB. 00 00 00 00 0 important colors 0 means all colors are important > > > > > > NB. Start of pixel array (bitmap data) > > > > > > NB. 00 00 FF 0 0 255 Red, Pixel (0,1) > > > > > > NB. FF FF FF 255 255 255 White, Pixel (1,1) > > > > > > NB. 00 00 0 0 Padding for 4 byte alignment (could be a value other than > > > zero) > > > > > > NB. FF 00 00 255 0 0 Blue, Pixel (0,0) > > > > > > NB. 00 FF 00 0 255 0 Green, Pixel (1,0) > > > > > > NB. 00 00 0 0 Padding for 4 byte alignment (could be a value other than > > > zero) > > > > > > NB. ) > > > > > > > > > smoutput $ hextable > > > > > > > > > process=: 3 : 0 > > > > > > z=. '' > > > > > > for_line. y do. > > > > > > z=.z , SP, TAB taketo line > > > > > > end. > > > > > > ;dec each b4o deb z > > > > > > ) > > > > > > smoutput process hextable > > > > > > > > > contents=: a.{~ process hextable > > > > > > > > > smoutput 'bytes written:' ; contents fwrite jpath '~/example1b.bmp' > > > > > > > > > > > > > > > On Tue, 4 Oct 2022 at 02:09, bill lam <[email protected]> wrote: > > > > > > > What's the spec of apple compliant bmp format? > > > > > > > > On Tue, Oct 4, 2022, 9:00 AM Ian Clark <[email protected]> > wrote: > > > > > > > > > Following recent security updates to macOS and iPadOS, they now > > refuse > > > to > > > > > display bitmaps generated by addon graphics/bmp, or any bitmaps > > shipped > > > > > with j904. For example: > > > /Applications/j904/addons/graphics/bmp/toucan.bmp > > > > > > > > > > However, if I copy this BMP file to my iCloud Drive, I can display > it > > > > okay > > > > > on a pre-Monterey macOS. This applies to all BMPs in the latest > > addons > > > > > folder (I count 11 such files). > > > > > > > > > > Other image formats: .jpg, .png are not affected (not fully > tested). > > > > > > > > > > BUT macOS and iPadOS do still display bitmaps. I've verified this > by > > > > > generating one of the sample BMP files published in > > > > > https://en.wikipedia.org/wiki/BMP_file_format > > > > > I'm happy to post my code, but it's only noise at this stage. The > > point > > > > is: > > > > > Apple has not withdrawn support for BMP, but tightened its checks > for > > > > > compliance with the spec. > > > > > > > > > > This has broken viewmat in j901-for-iOS. > > > > > > > > > > It would be good to fix addon: graphics/bmp to generate > > Apple-compliant > > > > > BMPs, and replace the bad BMPs in all addons shipped with j904. > That > > > > would > > > > > allow users to fix viewmat in j901-for-iOS without having to wait > for > > > the > > > > > bug release. But I cannot find the bug in graphics/bmp. > > > > > > > > > > In an earlier thread, I promised to take the matter up with Apple. > I > > > did, > > > > > but their reply is overdue. > > > > > > > > > > I am aware that viewmat in jqt now uses PNG not BMP. I confirm that > > the > > > > > latest version of graphics/viewmat generates correct PNGs which > > display > > > > > okay on iPadOS, using the Files app. But j901-for-iOS needs Swift > > > > > code-changes and a full re-install from App Store before it can > > > correctly > > > > > handle the resulting ~temp/viewmat.png which will replace > > > ~temp/vmat.bmp > > > > . > > > > > Simple in principle but messy in practice. I haven't worked out how > > > best > > > > to > > > > > do it. > > > > > > > > > > Ian Clark > > > > > > > ---------------------------------------------------------------------- > > > > > For information about J forums see > > http://www.jsoftware.com/forums.htm > > > > > > > > > > ---------------------------------------------------------------------- > > > > For information about J forums see > http://www.jsoftware.com/forums.htm > > > > > > > ---------------------------------------------------------------------- > > > For information about J forums see http://www.jsoftware.com/forums.htm > > > > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
