From d6891a58f907d075399cd6a41edbfa3bfc41e0a0 Mon Sep 17 00:00:00 2001
From: Ifenna Awagu <jawagu@gmail.com>
Date: Sat, 13 Apr 2019 22:19:09 +0100
Subject: [PATCH] Initial commit

---
 .gitignore         |  1 +
 lines/bresenham.go | 11 +++++++++++
 main.go            | 37 +++++++++++++++++++++++++++++++++++++
 window.go          | 44 ++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 93 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 lines/bresenham.go
 create mode 100644 main.go
 create mode 100644 window.go

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..62c8935
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.idea/
\ No newline at end of file
diff --git a/lines/bresenham.go b/lines/bresenham.go
new file mode 100644
index 0000000..c1effa9
--- /dev/null
+++ b/lines/bresenham.go
@@ -0,0 +1,11 @@
+package lines
+
+import "github.com/go-gl/gl/all-core/gl"
+
+func DrawPixel(x float32, y float32) {
+	gl.PointSize(10)
+	gl.Begin(gl.POINTS)
+	gl.Color3f(1.0, 1.0, 1.0)
+	gl.Vertex2f(x, y)
+	gl.End()
+}
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..d038218
--- /dev/null
+++ b/main.go
@@ -0,0 +1,37 @@
+package main
+
+import (
+	"github.com/go-gl/gl/all-core/gl"
+	"github.com/go-gl/glfw/v3.2/glfw"
+	"go-graphics/lines"
+	"runtime"
+)
+
+func init() {
+	runtime.LockOSThread()
+}
+
+func main() {
+	window := buildWindow()
+	defer glfw.Terminate()
+
+	program := initOpenGL()
+
+	for !window.ShouldClose() {
+		draw(window, program)
+	}
+
+}
+
+func draw(window *glfw.Window, program uint32) {
+	gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
+	gl.UseProgram(program)
+
+	//gl.LoadIdentity()
+	//gl.Ortho(0, 0, 0, 0, 0, 0)
+
+	lines.DrawPixel(0, 0)
+
+	window.SwapBuffers() // swap rendering and drawing buffers
+	glfw.PollEvents()    // poll input events
+}
diff --git a/window.go b/window.go
new file mode 100644
index 0000000..3481dae
--- /dev/null
+++ b/window.go
@@ -0,0 +1,44 @@
+package main
+
+import (
+	"fmt"
+	"github.com/go-gl/gl/all-core/gl"
+	"github.com/go-gl/glfw/v3.2/glfw"
+	"log"
+)
+
+func buildWindow() *glfw.Window {
+	if err := glfw.Init(); err != nil {
+		panic(fmt.Errorf("couldn't initialize glfw: %v", err))
+	}
+
+	setWindowHints()
+
+	window, err := glfw.CreateWindow(800, 600, "Graphics", nil, nil)
+	if err != nil {
+		panic(fmt.Errorf("could not create opengl renderer: %v", err))
+	}
+	window.MakeContextCurrent()
+
+	return window
+}
+
+func initOpenGL() uint32 {
+	if err := gl.Init(); err != nil {
+		panic(err)
+	}
+	version := gl.GoStr(gl.GetString(gl.VERSION))
+	log.Println("OpenGL version", version)
+
+	program := gl.CreateProgram()
+	gl.LinkProgram(program)
+	return program
+}
+
+func setWindowHints() {
+	glfw.WindowHint(glfw.ContextVersionMajor, 2)
+	glfw.WindowHint(glfw.ContextVersionMinor, 1)
+	glfw.WindowHint(glfw.Resizable, glfw.True)
+	//glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)
+	//glfw.WindowHint(glfw.OpenGLForwardCompatible, glfw.True)
+}