julia opengl

main.jl

using GLFW
using ModernGL

# NO COPY AND PASTE!!!
# CLEAN CODE IS GOOD CODE

# Create Window with size and title
GLFW.Init()
window = GLFW.CreateWindow(400, 300, "Title")

hints = Dict(GL_SAMPLES => 4,
             GL_MAJOR_VERSION => 3,
             GL_MINOR_VERSION => 3)


GLFW.MakeContextCurrent(window)

# Register Callbacks
# TODO: Make this a bit nicer :)
GLFW.SetKeyCallback(window, (window, key, scancode, action, mods) -> begin
    println("$window, $key, $scancode, $action, $mods")
    if key != GLFW.KEY_UNKNOWN
        if key == GLFW.KEY_ESCAPE && action == GLFW.PRESS
            println("Goodbye!")
            GLFW.DestroyWindow(window)
            exit()
        end 
    end
end)


# Setup Triangle / Vertex Data
data = GLfloat[
    0.0, 0.5,
    0.5, 0.0,
    0.0, 5.0
]

# Setup VAO
vao = GLuint[0]
glGenVertexArrays(1, vao)
vao = vao[]

println(typeof(vao))
println(glGetError())

# Why do we run this?
glBindVertexArray(vao)


# Create VBO and load the buffer with our vertex data
vbo = GLuint[0]
glGenBuffers(1, vbo)
vbo = vbo[]

# Bind ~= Make Current
glBindBuffer(GL_ARRAY_BUFFER, vbo)
glBufferData(GL_ARRAY_BUFFER, sizeof(data), data, GL_STATIC_DRAW)

# Define shaders
const vertex_shader = """
in vec2 position;
void main() {
    gl_Position = vec4(position, 0.0, 1.0);
}
"""

const frag_shader = """
out vec4 color;
void main() {
    outColor = vec4(1.0, 1.0, 1.0, 0.0);
}
"""

# OH GOD MAKING SHADERS IS ALWAYS A CHORE GOD DAMN
vertex_shader_id = glCreateShader(GL_VERTEX_SHADER)::GLuint
fragment_shader_id = glCreateShader(GL_FRAGMENT_SHADER)::GLuint

glShaderSource(vertex_shader_id, 1, convert(Ptr{UInt32}), pointer([convert(Ptr{GLchar}), pointer(vertex)]))


while !GLFW.WindowShouldClose(window)
    GLFW.SwapBuffers(window)
    glClear(GL_COLOR_BUFFER_BIT)

    glEnableVertexAttribArray(0)
    glBindBuffer(GL_ARRAY_BUFFER, vbo)
    glVertexAttribPointer(
        0,          # ????
        3,          # Size of array
        GL_FLOAT,   # Data Type
        GL_FALSE,   # Normalized?
        0,          # Stride
        C_NULL
    )

    glDrawArrays(GL_TRIANGLES, 0, 3) # From 0 to 3
    glDisableVertexAttribArray(0)

    GLFW.PollEvents()
end

GLFW.DestroyWindow(window)