r6819:linux:minibug in display/viewport.cc

[isidoro]

The floor function in display/viewport.cc requires to

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#include <cmath>
to compile.

[Ters]

Or rather math.h, which is more in the style of the other includes.

[kierongreen]

Fixed in 6820 (along with some accidental climate code which will be tidied up shortly...)

[Dwachs]

Is this piece of code

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found_i = ((int)floor(base_i/(double)rw4)) + i_off;

not equivalent to

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found_i = base_i / rw4 + i_off;

?? Integer division does the rounding it self.

Or maybe

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found_i = (base_i + rw4*i_off) / rw4;


[kierongreen]

Code Select Expand

found_i = base_i / rw4 + i_off;
does not give identical values

however

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found_i = (base_i + rw4*i_off) / rw4;
does give the same result so I've changed the code to this in 6822 and removed the math.h header include. Actually I've also moved the rw4*i_off to outside the height loop as that should be marginally more efficient...

[Markohs]

I come back to the forum and you already identified and repaired the bug! oh boy, good! Thx.

[isidoro]

Thank you all.