Okay...I'll try to explain, but you were warned! ;o)
When the video card converts a 32bit image to 16bits the two most common methods are:
1)The lowest 3bits are chopped off the end of each of the red, green and blue values (giving 15bits). The so called 555 format.
2)The lower 3bit of the red and blue and the lower 2 bits of the green are chopped off (giving 16bits). The so called 565 format.
The combined values are then slapped into the required 16bits (the 555 format doesn't use the top bit).
So, when Blitz reads a 16bit value it's really returning...
(8 bits red AND $F8) for red
(8 bits blue AND $F8) for blue
(8 bits green AND $F8/$FC) for green (depending on the video card)
I do believe 565 is the most common mode used.
BTW, $5F AND $FC is $5C so it seems your card uses 565.
Yan
When the video card converts a 32bit image to 16bits the two most common methods are:
1)The lowest 3bits are chopped off the end of each of the red, green and blue values (giving 15bits). The so called 555 format.
2)The lower 3bit of the red and blue and the lower 2 bits of the green are chopped off (giving 16bits). The so called 565 format.
The combined values are then slapped into the required 16bits (the 555 format doesn't use the top bit).
So, when Blitz reads a 16bit value it's really returning...
(8 bits red AND $F8) for red
(8 bits blue AND $F8) for blue
(8 bits green AND $F8/$FC) for green (depending on the video card)
I do believe 565 is the most common mode used.
BTW, $5F AND $FC is $5C so it seems your card uses 565.
Yan