forcegraph: fix rendering on hidpi devices
forcegraph: fix rendering on hidpi devices

freifunk-mwu/meshviewer,ffnord/meshviewer,freifunk-mwu/meshviewer,Freifunk-Troisdorf/meshviewer,max-weller/meshviewer,ffrgb/meshviewer,rubo77/meshviewer,yayachiken/hopglass,ffac/meshviewer,ffrgb/meshviewer,srauscher/hopglass,tcatm/meshviewer,ffnord/meshviewer,rubo77/meshviewer-compilation,hopglass/ffrgb-meshviewer,Freifunk-Rhein-Neckar/meshviewer,ffac/meshviewer_old,xf-/meshviewer-1,yayachiken/hopglass,Freifunk-Luxembourg/hopglass,rubo77/meshviewer-1,FreifunkBremen/meshviewer-ffrgb,Skrupellos/meshviewer,TVLuke/meshviewer,mayflower/meshviewer,Freifunk-Rhein-Neckar/meshviewer,rubo77/meshviewer,gherber/hopglass,Little-Ben/meshviewer,Little-Ben/meshviewer,Freifunk-Troisdorf/meshviewer,plumpudding/hopglass,FreifunkBremen/meshviewer-ffrgb,FreiFunkMuenster/meshviewer,tcatm/meshviewer,freifunkMUC/meshviewer,rubo77/meshviewer-1,freifunk-fulda/meshviewer,FreiFunkMuenster/meshviewer,hopglass/ffrgb-meshviewer,rubo77/meshviewer-compilation,ffac/meshviewer_old,tcatm/meshviewer,srauscher/hopglass,mayflower/meshviewer,TVLuke/meshviewer,FreifunkMD/Meshviewer,nonchip/meshviewer,Skrupellos/meshviewer,ffac/meshviewer,xf-/meshviewer-1,Freifunk-Rhein-Neckar/meshviewer,hopglass/hopglass,freifunk-mwu/meshviewer,nickel715/meshviewer,nickel715/meshviewer,freifunk-fulda/meshviewer,plumpudding/hopglass,kgbvax/meshviewer,freifunkMUC/meshviewer,TVLuke/meshviewer,Freifunk-Luxembourg/hopglass,gherber/hopglass,max-weller/meshviewer,ffac/meshviewer,FreiFunkMuenster/meshviewer,nonchip/meshviewer,hopglass/hopglass,nonchip/meshviewer,ffnord/meshviewer,kgbvax/meshviewer,FreifunkMD/Meshviewer