gg: add linux support for fn screen_size() Size fix (#23146)

.github/workflows/gg_regressions_ci.yml

@@ -45,7 +45,7 @@ jobs:
           # libgl1-mesa-dri          : For headless rendering / software DRI driver (LIBGL_ALWAYS_SOFTWARE=true)
           # freeglut3-dev            : Fixes graphic apps compilation with tcc
           ./v retry -- sudo apt update
-          ./v retry -- sudo apt install imagemagick openimageio-tools libgl1-mesa-dri xvfb libxcursor-dev libxi-dev freeglut3-dev xsel xclip
+          ./v retry -- sudo apt install imagemagick openimageio-tools libgl1-mesa-dri xvfb libxcursor-dev libxi-dev libxrandr-dev freeglut3-dev xsel xclip
           ./v retry -- ./v download https://raw.githubusercontent.com/tremby/imgur.sh/c98345d/imgur.sh
           ./v retry -- git clone https://github.com/Larpon/gg-regression-images gg-regression-images
           chmod +x ./imgur.sh

.github/workflows/other_ci.yml

@@ -101,7 +101,7 @@ jobs:
         run: |
           ./v retry -- sudo apt update
           ./v retry -- sudo apt install --quiet -y libsodium-dev libssl-dev sqlite3 libsqlite3-dev postgresql libpq-dev valgrind
-          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libasound2-dev xfonts-75dpi xfonts-base
+          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev xfonts-75dpi xfonts-base
           ./v retry -- sudo apt install --quiet -y g++-9 g++-10
 
       - name: g++-9 version

.github/workflows/sanitized_ci.yml

@@ -90,7 +90,7 @@ jobs:
         run: |
           ./v retry -- sudo apt update
           ./v retry -- sudo apt install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind
-          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libasound2-dev
+          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev
           ./v retry -- sudo apt install clang
       - name: Recompile V with -cstrict
         run: ./v -cg -cstrict -o v cmd/v
@@ -116,7 +116,7 @@ jobs:
         run: |
           ./v retry -- sudo apt update
           ./v retry -- sudo apt install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind
-          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libasound2-dev
+          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev
       - name: Recompile V with -cstrict
         run: ./v -cg -cstrict -o v cmd/v
       - name: Self tests (-fsanitize=undefined)
@@ -141,7 +141,7 @@ jobs:
         run: |
           ./v retry -- sudo apt update
           ./v retry -- sudo apt install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind
-          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libasound2-dev
+          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev
           ./v retry -- sudo apt install clang
       - name: Recompile V with -cstrict
         run: ./v -cg -cstrict -o v cmd/v
@@ -194,7 +194,7 @@ jobs:
         run: |
           ./v retry -- sudo apt update
           ./v retry -- sudo apt install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind
-          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libasound2-dev
+          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev
           ./v retry -- sudo apt install clang
       - name: Recompile V with -cstrict
         run: ./v -cg -cstrict -o v cmd/v
@@ -224,7 +224,7 @@ jobs:
         run: |
           ./v retry -- sudo apt update
           ./v retry -- sudo apt install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind
-          ./v retry -- sudo apt install --quiet -y libfreetype6-dev  libxi-dev libxcursor-dev libgl-dev libasound2-dev
+          ./v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev
           ./v retry -- sudo apt install clang
       - name: Recompile V with clang and -cstrict
         run: ./v -cc clang -cg -cstrict -o v cmd/v

.github/workflows/v_apps_and_modules_compile_ci.yml

@@ -40,7 +40,7 @@ jobs:
           if [ $RUNNER_OS == 'Linux' ]; then
             v retry -- sudo apt -qq update
             v retry -- sudo apt -qq install libgc-dev libsodium-dev libssl-dev sqlite3 libsqlite3-dev
-            v retry -- sudo apt -qq install libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libasound2-dev xfonts-75dpi xfonts-base
+            v retry -- sudo apt -qq install libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev xfonts-75dpi xfonts-base
             v retry -- sudo apt -qq install sassc libgit2-dev # needed by gitly
           else
             v retry brew install sassc libgit2

.github/workflows/vsl_and_vtl_compile_ci.yml

@@ -41,7 +41,7 @@ jobs:
           v retry -- sudo apt -qq update
           v retry -- sudo apt -qq install \
             libgc-dev libgl1-mesa-dev mesa-common-dev liblapacke-dev libopenblas-dev libopenmpi-dev \
-            opencl-headers libxcursor-dev libxi-dev libhdf5-cpp-103 libhdf5-dev libhdf5-mpi-dev hdf5-tools
+            opencl-headers libxcursor-dev libxi-dev libxrandr-dev libhdf5-cpp-103 libhdf5-dev libhdf5-mpi-dev hdf5-tools
           else
             v retry brew install coreutils hdf5 open-mpi openblas lapack opencl-headers
           fi

README.md

@@ -266,16 +266,21 @@ v run news_fetcher.v
 v run tetris/tetris.v
 ```
 
+
 <img src='https://raw.githubusercontent.com/vlang/v/master/examples/tetris/screenshot.png' width=300 alt='tetris screenshot'>
 
-In order to build Tetris or 2048 (or anything else using `sokol` or `gg` graphics modules),
-you will need additional development libraries for your system.
+## Sokol and GG GUI apps/games:
+
+In order to build Tetris or 2048 (or anything else using the `sokol` or `gg` graphics modules),
+you will need to install additional development libraries for your system.
 
 | System              | Installation method                                                                                |
 |---------------------|----------------------------------------------------------------------------------------------------|
-| Debian/Ubuntu based | `sudo apt install libxi-dev libxcursor-dev libgl-dev libasound2-dev`                               |
-| Fedora/RH/CentOS    | `sudo dnf install libXcursor-devel libXi-devel libX11-devel libglvnd-devel`                        |
-| NixOS               | add `xorg.libX11.dev xorg.libXcursor.dev xorg.libXi.dev libGL.dev` to `environment.systemPackages` |
+| Debian/Ubuntu based | Run `sudo apt install libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev`             |
+| Fedora/RH/CentOS    | Run `sudo dnf install libXi-devel libXcursor-devel libX11-devel libXrandr-devel libglvnd-devel`    |
+|                     |                                                                                                    |
+| NixOS               | Add `xorg.libX11.dev xorg.libXcursor.dev xorg.libXi.dev xorg.libXrandr.dev libGL.dev` to           |
+|                     | to `environment.systemPackages`                                                                    |
 
 ## V net.http, net.websocket, `v install`
 

ci/linux_ci.vsh

@@ -58,7 +58,7 @@ fn build_v_with_prealloc() {
 fn install_dependencies_for_examples_and_tools_tcc() {
 	exec('v retry -- sudo apt update')
 	exec('v retry -- sudo apt install --quiet -y libssl-dev sqlite3 libsqlite3-dev valgrind')
-	exec('v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libasound2-dev')
+	exec('v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev')
 	// The following is needed for examples/wkhtmltopdf.v
 	exec('v retry -- wget https://github.com/wkhtmltopdf/packaging/releases/download/0.12.6-1/wkhtmltox_0.12.6-1.focal_amd64.deb')
 	exec('v retry -- sudo apt install --quiet -y xfonts-75dpi xfonts-base')
@@ -171,7 +171,7 @@ fn all_code_is_formatted_gcc() {
 fn install_dependencies_for_examples_and_tools_gcc() {
 	exec('v retry -- sudo apt update')
 	exec('v retry -- sudo apt install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind')
-	exec('v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libasound2-dev')
+	exec('v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev')
 }
 
 fn recompile_v_with_cstrict_gcc() {
@@ -287,7 +287,7 @@ fn all_code_is_formatted_clang() {
 fn install_dependencies_for_examples_and_tools_clang() {
 	exec('v retry -- sudo apt update')
 	exec('v retry -- sudo apt install --quiet -y postgresql libpq-dev libssl-dev sqlite3 libsqlite3-dev valgrind')
-	exec('v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libasound2-dev')
+	exec('v retry -- sudo apt install --quiet -y libfreetype6-dev libxi-dev libxcursor-dev libgl-dev libxrandr-dev libasound2-dev')
 	exec('v retry -- sudo apt install --quiet -y clang')
 }
 

examples/tetris/README.md

@@ -5,6 +5,7 @@
 sudo apt install libx11-dev
 sudo apt install libxi-dev
 sudo apt install libxcursor-dev
+sudo apt install libxrandr-dev
 sudo apt install libgl-dev
 ```
 

vlib/gg/gg.c.v

@@ -10,6 +10,40 @@ import sokol.sapp
 import sokol.sgl
 import sokol.gfx
 
+@[typedef]
+struct C.XRRScreenResources {
+	noutput int
+	outputs &int
+}
+
+@[typedef]
+struct C.XRROutputInfo {
+	crtc u64
+}
+
+@[typedef]
+struct C.XRRCrtcInfo {
+	width  u32
+	height u32
+}
+
+fn C.XOpenDisplay(int) voidptr
+fn C.XCloseDisplay(voidptr) int
+fn C.DefaultScreen(voidptr) int
+fn C.DefaultRootWindow(voidptr) u64
+fn C.XRRGetScreenResources(voidptr, u64) &C.XRRScreenResources
+fn C.XRRGetOutputPrimary(voidptr, u64) u64
+fn C.XRRFreeScreenResources(&C.XRRScreenResources)
+fn C.XRRGetOutputInfo(voidptr, &C.XRRScreenResources, u64) &C.XRROutputInfo
+fn C.XRRFreeOutputInfo(&C.XRROutputInfo)
+fn C.XRRGetCrtcInfo(voidptr, &C.XRRScreenResources, u64) &C.XRRCrtcInfo
+fn C.XRRFreeCrtcInfo(&C.XRRCrtcInfo)
+
+$if linux {
+	#flag -lXrandr
+	#include <X11/extensions/Xrandr.h>
+}
+
 $if windows {
 	#flag -lgdi32
 	#include "windows.h"
@@ -739,7 +773,41 @@ pub fn screen_size() Size {
 			height: int(C.GetSystemMetrics(C.SM_CYSCREEN))
 		}
 	}
-	// TODO: linux, etc
+	$if linux {
+		display := C.XOpenDisplay(0)
+		if display == unsafe { nil } {
+			return Size{}
+		}
+		defer { C.XCloseDisplay(display) }
+		root := C.DefaultRootWindow(display)
+		resources := C.XRRGetScreenResources(display, root)
+		if resources == unsafe { nil } {
+			return Size{}
+		}
+		defer { C.XRRFreeScreenResources(resources) }
+		primary_output := C.XRRGetOutputPrimary(display, root)
+		if primary_output == 0 {
+			return Size{}
+		}
+		for i := 0; i < resources.noutput; i++ {
+			if unsafe { u64(resources.outputs[i]) } == primary_output {
+				output_info := C.XRRGetOutputInfo(display, resources, unsafe { resources.outputs[i] })
+				if output_info == unsafe { nil } {
+					return Size{}
+				}
+				defer { C.XRRFreeOutputInfo(output_info) }
+				crtc_info := C.XRRGetCrtcInfo(display, resources, output_info.crtc)
+				if crtc_info == unsafe { nil } {
+					return Size{}
+				}
+				defer { C.XRRFreeCrtcInfo(crtc_info) }
+				return Size{
+					width:  unsafe { int(crtc_info.width) }
+					height: unsafe { int(crtc_info.height) }
+				}
+			}
+		}
+	}
 	return Size{}
 }