OGLplus (0.52.0) a C++ wrapper for OpenGL

oglplus/002_triangle.cpp

Shows the basic usage of OGLplus by drawing a simple triangle.

002_triangle.png

Copyright 2008-2014 Matus Chochlik. Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

#include <oglplus/gl.hpp>
#include <oglplus/all.hpp>
#include "example.hpp"
namespace oglplus {
class TriangleExample : public Example
{
private:
// wrapper around the current OpenGL context
Context gl;
// Vertex shader
// Fragment shader
// Program
Program prog;
// A vertex array object for the rendered triangle
VertexArray triangle;
// VBOs for the triangle's vertices and colors
Buffer verts;
Buffer colors;
public:
TriangleExample(void)
{
// Set the vertex shader source
vs.Source(" \
#version 330\n \
in vec3 Position; \
in vec3 Color; \
out vec4 vertColor; \
void main(void) \
{ \
gl_Position = vec4(Position, 1.0); \
vertColor = vec4(Color, 1.0); \
} \
");
// compile it
vs.Compile();
// set the fragment shader source
fs.Source(" \
#version 330\n \
in vec4 vertColor; \
out vec4 fragColor; \
void main(void) \
{ \
fragColor = vertColor; \
} \
");
// compile it
fs.Compile();
// attach the shaders to the program
prog.AttachShader(vs);
prog.AttachShader(fs);
// link and use it
prog.Link();
prog.Use();
// bind the VAO for the triangle
triangle.Bind();
GLfloat triangle_verts[9] = {
0.0f, 0.0f, 0.0f,
1.0f, 0.0f, 0.0f,
0.0f, 1.0f, 0.0f
};
// bind the VBO for the triangle vertices
verts.Bind(Buffer::Target::Array);
// upload the data
Buffer::Data(Buffer::Target::Array, 9, triangle_verts);
// setup the vertex attribs array for the vertices
VertexArrayAttrib(prog, "Position").Setup<GLfloat>(3).Enable();
//
GLfloat triangle_colors[9] = {
1.0f, 0.0f, 0.0f,
0.0f, 1.0f, 0.0f,
0.0f, 0.0f, 1.0f
};
// bind the VBO for the triangle colors
colors.Bind(Buffer::Target::Array);
// upload the data
Buffer::Data(Buffer::Target::Array, 9, triangle_colors);
// setup the vertex attribs array
VertexArrayAttrib(prog, "Color").Setup<GLfloat>(3).Enable();
gl.ClearColor(1.0f, 1.0f, 1.0f, 0.0f);
gl.Disable(Capability::DepthTest);
}
void Reshape(GLuint width, GLuint height)
{
gl.Viewport(width, height);
}
void Render(double)
{
gl.Clear().ColorBuffer();
gl.DrawArrays(PrimitiveType::Triangles, 0, 3);
}
};
void setupExample(ExampleParams& /*params*/){ }
std::unique_ptr<ExampleThread> makeExampleThread(
Example& /*example*/,
unsigned /*thread_id*/,
const ExampleParams& /*params*/
){ return std::unique_ptr<ExampleThread>(); }
std::unique_ptr<Example> makeExample(const ExampleParams& /*params*/)
{
return std::unique_ptr<Example>(new TriangleExample);
}
} // namespace oglplus

Copyright © 2010-2014 Matúš Chochlík, University of Žilina, Žilina, Slovakia.
<matus.chochlik -at- fri.uniza.sk>
<chochlik -at -gmail.com>
Documentation generated on Mon Sep 22 2014 by Doxygen (version 1.8.6).