slideshow fails with error CreateIconIndirect: call failed (87)

[spdegabrielle]

Using slideshow on some windows 10 machines results in the following error:

CreateIconIndirect: call failed (87)
Interactions disabled: slideshow does not support a REPL (no #%top-interaction)

The interim means to resolve this error is at https://groups.google.com/d/msg/racket-users/vYVaGAff1o8/gBjuCCjdAQAJ

Instruction to reproduce https://groups.google.com/d/msg/racket-users/vYVaGAff1o8/xzXy4xQ6AgAJ

the minimal program which reproduces the issue on Windows 10, version1809:

#lang racket/gui
(require racket/draw)

(define f (new frame% [label "hello"] [width 100] [height 100]))

(define bmp
  (let* ([bm (make-object bitmap% 32 32)]
         [dc (make-object bitmap-dc% bm)])
    (send dc set-brush "red" 'solid)
    (send dc draw-rectangle 0 0 (send bm get-width) (send bm get-height))
    (send dc set-bitmap #f)
    bm))

(send f set-icon bmp #f 'both)
(send f show #t)

Any program which tries to set the icon on a frame will fail regardless of the icon. Slideshow fails because it tries to set the icon on the frame. It seems that the W32 API call CreateIconIndirect() fails because it thinks the bitmap passes in is invalid.

@mflatt noted:

It looks like the problem is that the main bitmap given to CreateIconIndirect is scaled, but the mask bitmap is not scaled (in bitmap->hbitmap). So, replicating the error also requires a high-resolution screen with scaling enabled.

(see thread linked above)

[mflatt]

Commit 3aa2d21 is intended to repair the problem.

[spdegabrielle]

@mflatt Thank you.

[mflatt]

@spdegabrielle Thanks for gathering all of the details for the record!