module Shader (drawShaderLay) where

import Control.Lens
import Control.Monad.Primitive
import qualified Data.Vector.Unboxed.Mutable as UMV
import Graphics.GL.Core45
import Shader.Data
import Shader.Parameters

drawShaderLay :: Int -> UMV.MVector (PrimState IO) Int -> Int -> (Shader, VBO) -> IO ()
{-# INLINE drawShaderLay #-}
drawShaderLay l countsVector shadIn fs = do
    i <- UMV.read countsVector shadIn
    glUseProgram (_shaderUINT $ fst fs)
    glBindVertexArray $ fs ^. _1 . shaderVAO . unVAO
    glDrawArrays
        (_unPrimitiveMode $ _shaderPrimitive $ fst fs)
        (fromIntegral $ l * numSubElements)
        (fromIntegral i)