skunkworks-c/subprojects/lpng1639/contrib/conftest/read.dfa

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2022-12-21 12:09:42 +01:00
# read.dfa
# Build time configuration of libpng
#
# Author: John Bowler
# Copyright: (c) John Bowler, 2013
# Usage rights:
# To the extent possible under law, the author has waived all copyright and
# related or neighboring rights to this work. This work is published from:
# United States.
#
# Build libpng with basic read support. This enables the lowest level libpng
# read API - the one where the calling code has to use a loop to read each row.
# At present this is the API used by most programs.
#
# Support is enabled only for those chunks and transformations that are
# typically required - others can be added easily.
#
everything = off
# The sequential read code is enabled here; the progressive code can be used
# instead but there is no point enabling both.
option SEQUENTIAL_READ on
# Likewise it is pointless enabling both fixed and floating point APIs. Choose
# one or the other for both the API and the internal math.
#Fixed point:
#option FIXED_POINT on
#option FLOATING_ARITHMETIC off
#Floating point:
option FLOATING_POINT on
option FLOATING_ARITHMETIC on
# Basic error handling, IO and user memory support. The latter allows the
# application program to provide its own implementations of 'malloc' and 'free'.
option SETJMP on
option STDIO on
option USER_MEM on
# To read the full set of PNG images correctly interlace, transparency and
# 16-bit support is required. The application can implement interlace itself,
# but very few do and it's no longer possible to disable it when READ is
# enabled.
option READ_tRNS on
option READ_16BIT on
# Everything else is application dependent. This file assumes the app handles
# all the native PNG bit layouts, so it doesn't need any of layout change
# transforms, but needs libpng to perform gamma correction. It doesn't do any
# colorspace stuff and ignores the 'significant bit' information.
#
# If your app always expands the image to a limited set of bit layouts you
# probably want to consider using the simplified API instead of the low level
# one - see png.h and s_read.dfa.
option READ_GAMMA on