GLAnnotate

Overview

GLAnnotate is a single header OpenGL utility for rapid prototyping and debug drawing in OpenGL. It gives you all the simple but slow things we miss from oldschool OpenGL such as matrix stacks and immediate mode drawing.

In addition to that it also supports custom vertex attributes.

Basic Example

//init the gla instance
gla::GLAnnotate gla;
bool success = gla.init();
assert(success);

//setup orthi projection
gla.ortho(0, 800, 600, 0, -1, 1);
gla.setColor(1.0, 0.5, 0.25);
gla.circle(400, 300, 100);

gla.setColor(0.25, 0.5, 1.0);
gla.rect(50, 50, 100, 100);

gla.setColor(1.0, 0.0, 0.0);
gla.line(100, 100, 400, 300);

//easy way to draw a texture (tex is an OpenGL texture handle, not initialized in this snippet)
gla.setColor(1.0, 1.0, 1.0);
gla.texture(tex, 400, 200, tw, th);

//draw a custom shape
gla.begin(GL_TRIANGLE_FAN);
gla.setColor(1.0, 1.0, 1.0);
gla.vertex(100, 200, 0);
gla.setColor(1.0, 0.0, 0.3);
gla.vertex(50, 200, 0);
gla.setColor(1.0, 1.0, 0.3);
gla.vertex(100, 100, 0);
gla.setColor(1.0, 0.25, 0.3);
gla.vertex(150, 200, 0);
gla.setColor(1.0, 0.25, 1.0);
gla.vertex(150, 300, 0);
gla.setColor(0.0, 0.25, 1.0);
gla.vertex(50, 300, 0);
gla.setColor(1.0, 0.0, 0.3);
gla.vertex(50, 200, 0);
gla.end();

Supported Platforms

Linux and OSX at this point in time. (should be trivial to add more)

Dependencies

OpenGL

License

MIT License.

Installation

Either install the header file in the default location:

mkdir build
cd build
cmake ..
make install

and then include it like this

#include <GLAnnotate/GLAnnotate.hpp>

Or simply copy the file into your project and include it from there!

Examples

The examples depend on GLFW to open a window.

To build the examples do the following:

mkdir build
cd build
cmake -DBuildExamples=On ..
make

and open them like this, i.e.:

cd Examples
./BasicExample