use super::*;
use super::errors::*;
use std::mem::uninitialized;
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
pub struct ProgramId(u32);
impl ProgramId {
pub fn empty() -> ProgramId {
ProgramId(0)
}
}
impl From<ProgramId> for u32 {
fn from(program_id: ProgramId) -> Self {
program_id.0
}
}
pub unsafe fn create_program() -> ProgramId {
ProgramId(gl::CreateProgram())
}
pub unsafe fn delete_program(id: ProgramId) {
gl::DeleteProgram(id.into());
}
pub unsafe fn attach_shader(program_id: ProgramId, shader_id: ShaderId) -> Result<()> {
gl::AttachShader(program_id.into(), shader_id.into());
get_error(())
}
pub unsafe fn detach_shader(program_id: ProgramId, shader_id: ShaderId) -> Result<()> {
gl::DetachShader(program_id.into(), shader_id.into());
get_error(())
}
pub unsafe fn link_program(id: ProgramId) -> Result<()> {
gl::LinkProgram(id.into());
get_error(())
}
pub unsafe fn get_program(id: ProgramId, parameter: ShaderProgramParameter) -> Result<i32> {
let mut value: gl::types::GLint = uninitialized();
gl::GetProgramiv(id.into(), parameter.into(), &mut value);
get_error(value)
}
pub unsafe fn get_program_info_log(id: ProgramId) -> Result<String> {
let mut error_log_size: gl::types::GLint =
get_program(id.into(), ShaderProgramParameter::InfoLogLength).chain_err(|| "Could not get log length")?;
let mut error_log: Vec<u8> = Vec::with_capacity(error_log_size as usize);
gl::GetProgramInfoLog(
id.into(),
error_log_size,
&mut error_log_size,
error_log.as_mut_ptr() as *mut gl::types::GLchar,
);
error_log.set_len(error_log_size as usize);
let string = match String::from_utf8(error_log) {
Ok(s) => s,
Err(_) => bail!("Could not convert log"),
};
Ok(string)
}
pub unsafe fn use_program(id: ProgramId) -> Result<()> {
gl::UseProgram(id.into());
get_error(())
}
pub unsafe fn get_program_linked(id: ProgramId) -> bool {
let link_status = get_program(id.into(), ShaderProgramParameter::LinkStatus).unwrap();
link_status == 1
}