Allegro 4: red/blue swapped after screen mode change

Allegro 4: red/blue swapped after screen mode change

Andrew Gillett

Member #15,868

January 2015

See screenshot. The red and blue channels have been swapped, excluding the green background which is drawn using clear_to_color. The sprites are drawn with draw_rle_sprite. This happens only very occasionally, after changing screen mode. The color depth is set to 32 bit at the start of the program and never changes. I have not found a way to consistently repro this.

bamccaig

Member #7,536

July 2006

Just FYI, you can embed images in the page using markdown (or XHTML) syntax:

[https://d1cxvcw9gjxu2x.cloudfront.net/attachments/612067]

becomes

{"name":"612067","src":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/7\/6\/764a192fc1b651b0f1bc5f05bac07f1a.png","w":1920,"h":1080,"tn":"\/\/djungxnpq2nug.cloudfront.net\/image\/cache\/7\/6\/764a192fc1b651b0f1bc5f05bac07f1a"}

--
I mean the best with what I say. It doesn't always sound that way.

Edgar Reynaldo

Major Reynaldo

May 2007

Allegro 4 isn't smart enough to automatically convert your bitmaps when the display format changes, so it has to do software conversion or no conversion at all, and simply because the display order is swapped, the colors will be swapped.

Simple remedy - reload all your images when changing display modes.

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