From 3e28700cebc6fa771c7fbc61bdd3f3266b6fab0e Mon Sep 17 00:00:00 2001
From: David Vereb <dvereb@dvereb.com>
Date: Thu, 21 May 2020 16:34:50 -0400
Subject: [PATCH] Initial Commit.

---
 .gitignore |  4 +++
 Makefile   |  2 ++
 main.cpp   | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 79 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 Makefile
 create mode 100644 main.cpp

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..1186b73
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+*~
+.o
+a.out
+
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..76444a0
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,2 @@
+a.out: main.cpp
+	clang++ -std=c++14 -g -o a.out main.cpp -lGL -lGLU -lglut
diff --git a/main.cpp b/main.cpp
new file mode 100644
index 0000000..d82ad9e
--- /dev/null
+++ b/main.cpp
@@ -0,0 +1,73 @@
+#include <iostream>
+#include <cstdlib>
+
+#include <GL/glut.h>
+
+GLfloat light_diffuse[] = {1.0, 0.0, 0.0, 1.0};  /* Red diffuse light. */
+GLfloat light_position[] = {1.0, 1.0, 1.0, 0.0};  /* Infinite light location. */
+
+void draw()
+{
+	glLineWidth(2.0f);
+	glColor3d(0,0,0);
+
+	float line[21];
+
+	for(auto i = 0; i < 21; ++i)
+		line[i] = 0;
+
+	for(auto y = 0; y < 100; ++y)
+	{
+		glBegin(GL_LINE_STRIP);
+		for(auto x = 0; x < 21; ++x)
+		{
+			line[x] += (rand() % 5 - 2) / 4.0f;
+			glVertex3f(x - 10, line[x], 25.0 - y);
+		}
+		glEnd();
+	}
+}
+
+void display()
+{
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+	draw();
+	glutSwapBuffers();
+}
+
+void init()
+{
+	// dvereb:
+	srand(time(NULL));
+
+	/* Enable a single OpenGL light. */
+	glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
+	glLightfv(GL_LIGHT0, GL_POSITION, light_position);
+	glEnable(GL_LIGHT0);
+	glEnable(GL_LIGHTING);
+
+	/* Use depth buffering for hidden surface elimination. */
+	glEnable(GL_DEPTH_TEST);
+
+	/* Setup the view of the cube. */
+	glMatrixMode(GL_PROJECTION);
+	gluPerspective( /* field of view in degree */ 40.0,
+	                /* aspect ratio */ 1.0,
+	                /* Z near */ 1.0, /* Z far */ 1000.0);
+	glMatrixMode(GL_MODELVIEW);
+	gluLookAt(0.0, 7.0, 25.0,  /* eye is at (0,0,5) */
+	          0.0, 0.0, 0.0,      /* center is at (0,0,0) */
+	          0.0, 1.0, 0.);      /* up is in positive Y direction */
+}
+
+int main(int argc, char *argv[])
+{
+	glutInit(&argc, argv);
+	glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
+	glutCreateWindow("test opengl program");
+	glutDisplayFunc(display);
+	init();
+	glutMainLoop();
+
+	return 0;
+}