From 466083852c94c2093cb3fcb7fc2ea24b2cfa611c Mon Sep 17 00:00:00 2001
From: Jeff Carr <jcarr@wit.com>
Date: Wed, 9 Jan 2019 04:13:45 -0800
Subject: [PATCH] make a clean file that just is for parsing the command line

Signed-off-by: Jeff Carr <jcarr@wit.com>
---
 .gitignore                               |  1 +
 community/seascape-shader/commandline.go | 67 ++++++++++++++++++++++++
 community/seascape-shader/seascape.go    | 34 ------------
 3 files changed, 68 insertions(+), 34 deletions(-)
 create mode 100644 .gitignore
 create mode 100644 community/seascape-shader/commandline.go

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..e3effb5
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+community/seascape-shader/seascape-shader
diff --git a/community/seascape-shader/commandline.go b/community/seascape-shader/commandline.go
new file mode 100644
index 0000000..8ceb8cc
--- /dev/null
+++ b/community/seascape-shader/commandline.go
@@ -0,0 +1,67 @@
+package main
+
+/* 
+	This simply parses the command line arguments using the default golang
+	package called 'flag'. This can be used as a simple template to parse
+	command line arguments in other programs.
+*/
+
+import "log"
+import "os"
+import "flag"
+import "fmt"
+
+var (
+	version       string
+	race          bool
+	debug         = os.Getenv("BUILDDEBUG") != ""
+	filename      string
+	width         int
+	height        int
+	timeout       = "120s"
+	uDrift        float32
+)
+
+var customUsage = func() {
+	fmt.Fprintf(flag.CommandLine.Output(), "Usage of %s:\n", os.Args[0])
+	flag.PrintDefaults()
+
+	fmt.Println("")
+	fmt.Println("EXAMPLE:")
+	fmt.Println("")
+	fmt.Println("seascape-shader --width 640 --height 480 --filename shaders/planetfall.glsl")
+	fmt.Println("")
+}
+
+func parseFlags() {
+	flag.StringVar  (&version,       "version",       "v0.1",                     "Set compiled in version string")
+	flag.StringVar  (&filename,      "filename",      "shaders/seascape.glsl",    "path to GLSL file")
+	flag.IntVar     (&width,         "width",         1024,                       "Width of the OpenGL Window")
+	flag.IntVar     (&height,        "height",        768,                        "Height of the OpenGL Window")
+	var tmp float64
+	flag.Float64Var (&tmp,           "drift",         0.01,                       "Speed of the gradual camera drift")
+	flag.BoolVar    (&race,          "race",          race,                       "Use race detector")
+
+	// Set the output if something fails to stdout rather than stderr
+	flag.CommandLine.SetOutput(os.Stdout)
+	// flag.SetOutput(os.Stdout)
+
+	flag.Usage = customUsage
+	flag.Parse()
+
+	if flag.Parsed() {
+		log.Println("Parsed() worked. width=",width)
+	} else {
+		log.Println("Parsed() failed. width=",width)
+	}
+
+//	if err := flag.Parse(); err != nil {
+//		log.Println("Example:",width)
+//	}
+		
+
+	uDrift = float32(tmp)
+	log.Println("width=",width)
+	log.Println("height=",height)
+	log.Println("uDrift=",uDrift)
+}
diff --git a/community/seascape-shader/seascape.go b/community/seascape-shader/seascape.go
index af3be62..2e2d4a9 100644
--- a/community/seascape-shader/seascape.go
+++ b/community/seascape-shader/seascape.go
@@ -2,7 +2,6 @@ package main
 
 import (
 	"time"
-	"log"
 
 	"github.com/go-gl/mathgl/mgl32"
 
@@ -11,20 +10,6 @@ import (
 	"golang.org/x/image/colornames"
 )
 
-import "flag"
-import "os"
-
-var (
-	version       string
-	race          bool
-	debug         = os.Getenv("BUILDDEBUG") != ""
-	filename      string
-	width         int
-	height        int
-	timeout       = "120s"
-	uDrift        float32
-)
-
 func run() {
 	// Set up window configs
 	cfg := pixelgl.WindowConfig{ // Default: 1024 x 768
@@ -86,25 +71,6 @@ func run() {
 
 }
 
-func parseFlags() {
-	flag.StringVar  (&version,       "version",       "v0.1",                     "Set compiled in version string")
-	flag.StringVar  (&filename,      "filename",      "shaders/seascape.glsl",    "path to GLSL file")
-	flag.IntVar     (&width,         "width",         1024,                       "Width of the OpenGL Window")
-	flag.IntVar     (&height,        "height",        768,                        "Height of the OpenGL Window")
-	var tmp float64
-	flag.Float64Var (&tmp,           "drift",         0.01,                       "Speed of the gradual camera drift")
-	flag.BoolVar    (&race,          "race",          race,                       "Use race detector")
-
-	// this parses the arguements
-	flag.Parse()
-
-	uDrift = float32(tmp)
-	log.Println("width=",width)
-	log.Println("height=",height)
-	log.Println("uDrift=",uDrift)
-
-}
-
 func main() {
 	parseFlags()