[orx-obj-loader] Add obj saver, demos (#348)

orx-obj-loader/src/demo/kotlin/DemoObjSaver01.kt

@@ -0,0 +1,22 @@
+import org.openrndr.application
+import org.openrndr.draw.loadFont
+import org.openrndr.extra.objloader.loadOBJasVertexBuffer
+import org.openrndr.extra.objloader.saveOBJ
+
+fun main() = application {
+    configure {
+        height = 100
+    }
+    program {
+        val path = "demo-data/obj-models"
+        val mesh = loadOBJasVertexBuffer("$path/suzanne/Suzanne.obj")
+        mesh.saveOBJ("$path/Suzanne-exported.obj")
+
+        val font = loadFont("demo-data/fonts/IBMPlexMono-Regular.ttf", 24.0)
+
+        extend {
+            drawer.fontMap = font
+            drawer.text(".obj file loaded and saved", 10.0, 80.0)
+        }
+    }
+}