load images and fonts from executing dir (#153)

* images and font should load from executing dir

* Add check to only use Sys if backend is native

src/Core/Environment.re

@@ -12,3 +12,8 @@ let sleep = (t: Time.t) =>
   if (isNative) {
     Unix.sleepf(Time.to_float_seconds(t));
   };
+
+let getExecutingDirectory = () =>
+  isNative ? Filename.dirname(Sys.argv[0]) ++ Filename.dir_sep : "";
+
+let getWorkingDirectory = () => Sys.getcwd();

src/UI/FontCache.re

@@ -1,14 +1,16 @@
+open Revery_Core;
 type fontInfo = (string, int);
 type t = Hashtbl.t(fontInfo, Fontkit.fk_face);
 
 let _cache: t = Hashtbl.create(100);
 
 let load = (fontName: string, size: int) => {
+  let execDir = Environment.getExecutingDirectory();
   let ret: Fontkit.fk_face =
     switch (Hashtbl.find_opt(_cache, (fontName, size))) {
     | Some(fk) => fk
     | None =>
-      let fk = Fontkit.load(fontName, size);
+      let fk = Fontkit.load(execDir ++ fontName, size);
       Hashtbl.add(_cache, (fontName, size), fk);
       fk;
     };

src/UI/ImageRenderer.re

@@ -1,5 +1,6 @@
 open Reglfw;
 open Reglfw.Glfw;
+open Revery_Core;
 
 type t = {
   mutable hasLoaded: bool,
@@ -14,8 +15,10 @@ let _cache: cache = Hashtbl.create(100);
 
 let getTexture = (imagePath: string) => {
   /* TODO: Support url paths? */
+  let execDir = Environment.getExecutingDirectory();
+  let relativeImagePath = execDir ++ imagePath;
 
-  let cacheResult = Hashtbl.find_opt(_cache, imagePath);
+  let cacheResult = Hashtbl.find_opt(_cache, relativeImagePath);
 
   let ret =
     switch (cacheResult) {
@@ -32,7 +35,7 @@ let getTexture = (imagePath: string) => {
       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
       glTexImage2D(GL_TEXTURE_2D, initialImage);
 
-      let imageLoadPromise = Image.load(imagePath);
+      let imageLoadPromise = Image.load(relativeImagePath);
 
       let success = img => {
         glBindTexture(GL_TEXTURE_2D, texture);
@@ -41,7 +44,7 @@ let getTexture = (imagePath: string) => {
       };
 
       let _ = Lwt.bind(imageLoadPromise, success);
-      Hashtbl.add(_cache, imagePath, texture);
+      Hashtbl.add(_cache, relativeImagePath, texture);
       texture;
     };