shader_update_bones   xtlang

(bind-func shader_update_bones
  (let ((bonesdat:float* (alloc (* 16 4 20))) ;; 16 (4x4 array) * 20 * 4 (bytes per float)
        (i:i32 0))
    ;; default to id matrix
    (dotimes (i 20) (fill_identity_matrix (pref-ptr bonesdat (* 16 i))))
    (lambda (shader:ShaderProgram* mesh:XTMMesh*)
      (let ((num_bones (tref mesh 12))
            (bones (tref mesh 13))
            (bone:XTMBone* null)
            (mymat:float* (alloc 16))
            (transmat:float* null))
        (fill_identity_matrix mymat)
        (translate_matrix mymat 2.0 2.0 2.0)
        ;; (dotimes (i 20) (fill_identity_matrix (pref-ptr bonesdat (* 16 i))))
        (dotimes (i num_bones)
          (set! bone (pref-ptr bones i))
          (set! transmat (tref bone 2))
          (memcpy (cast mymat i8*) (cast transmat i8*) (* 16 4))
          (if (= i -1)
              (begin
                (rotate_matrix mymat 50.0 0.0 1.0 0.0)
                (memcpy (cast (pref-ptr bonesdat (* 16 i)) i8*) (cast mymat i8*) (* 16 4)))
              (memcpy (cast (pref-ptr bonesdat (* 16 i)) i8*) (cast transmat i8*) (* 16 4))))
        ;; update 20 bones
        (glUniformMatrix4fv (glGetUniformLocation (id shader) "Bone") 20 GL_FALSE bonesdat)
        (gl_print_error "Error updating bones")
        void))))