vlib: handle some C. calls #19

	name: Graphics CI

	on:
	push:
	paths-ignore:
	- "**.md"
	pull_request:
	paths-ignore:
	- "**.md"

	jobs:
	gg-regressions:
	runs-on: ubuntu-20.04
	if: github.event_name != 'push' \|\| github.event.ref == 'refs/heads/master' \|\| github.event.repository.full_name != 'vlang/v'
	timeout-minutes: 20
	env:
	VFLAGS: -cc tcc
	DISPLAY: :99
	LIBGL_ALWAYS_SOFTWARE: true
	VTMP: /tmp
	steps:
	- name: Checkout V
	uses: actions/checkout@v3

	- name: Build local v
	run: make

	- name: Setup dependencies
	run: \|
	# imagemagick : convert, mogrify
	# xvfb : xvfb
	# openimageio-tools : idiff
	# libxcursor-dev libxi-dev : V gfx deps
	# libgl1-mesa-dri : For headless rendering / software DRI driver (LIBGL_ALWAYS_SOFTWARE=true)
	# freeglut3-dev : Fixes graphic apps compilation with tcc
	sudo apt-get update
	sudo apt-get install imagemagick openimageio-tools libgl1-mesa-dri xvfb libxcursor-dev libxi-dev freeglut3-dev xsel xclip
	wget https://raw.githubusercontent.com/tremby/imgur.sh/c98345d/imgur.sh
	git clone https://github.com/Larpon/gg-regression-images gg-regression-images
	chmod +x ./imgur.sh

	- name: Sample and compare
	id: compare
	continue-on-error: true
	run: \|
	Xvfb $DISPLAY -screen 0 1280x1024x24 -fbdir /var/tmp/ &
	sleep 1; while [ ! -f /var/tmp/Xvfb_screen0 ]; do sleep 0.5; done # give xvfb time to start, even on slow CI runs
	sleep 1; ./v gret -t ./gg-regression-images/vgret.v_examples.toml -v ./gg-sample_images ./gg-regression-images

	- name: Upload regression to imgur
	if: steps.compare.outcome != 'success'
	run: \|
	./imgur.sh /tmp/fail.png
	./imgur.sh /tmp/diff.png
	exit 1

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