shader.zig

var direct_allocator = std.heap.DirectAllocator.init();
var allocator = &direct_allocator.allocator;

fn initShaders() void {
    const program = c.glCreateProgram();

    const vsrc =
        c\\#version 300
        c\\in vec3 position;
        c\\out vec3 vecPosition;
        c\\
        c\\void main() {
        c\\  vecPosition = position;
        c\\  gl_Position = vec3(poostion, 1.0);
        c\\}
        ;

    const vshader = createShader(c.GL_VERTEX_SHADER, vsrc);
}

fn createShader(shader_type: c.GLenum, source: [*]const u8) c.GLuint {
    const shader = c.glCreateShader(shader_type);
    const srcArr = [][*]const u8 { source };

    c.glShaderSource(shader, 1, &srcArr, null);
    c.glCompileShader(shader);

    const log = getShaderInfoLog(shader);

    warn("Log {}\n", log);

    return shader;
}

fn getShaderiv(shader: c.GLuint, param: c.GLenum) i32 {
    var temp: [1]i32 = []i32 { 0 };

    c.glGetShaderiv(shader, param, &temp);

    return temp[0];
}

fn getShaderInfoLog(shader: c.GLuint) ![]const u8 {
    const log_length = getShaderiv(shader, c.GL_INFO_LOG_LENGTH);

    var buffer = try allocator.alloc(u8, @intCast(usize, log_length));
    var temp: [1]i32 = []i32 { 0 };

    c.glGetShaderInfoLog(shader, log_length, &temp, @ptrCast([*]u8, &buffer));

    return buffer;
}