Function RenderPrimitivesEx

Source/3rdParty/implot/implot_items.cpp:1487–1523

/// Renders primitive shapes in bulk as efficiently as possible.
template <class _Renderer>
void RenderPrimitivesEx(const _Renderer& renderer, ImDrawList& draw_list, const ImRect& cull_rect) {
    unsigned int prims        = renderer.Prims;
    unsigned int prims_culled = 0;
    unsigned int idx          = 0;
    renderer.Init(draw_list);
    while (prims) {
        // find how many can be reserved up to end of current draw command's limit
        unsigned int cnt = ImMin(prims, (MaxIdx<ImDrawIdx>::Value - draw_list._VtxCurrentIdx) / renderer.VtxConsumed);
        // make sure at least this many elements can be rendered to avoid situations where at the end of buffer this slow path is not taken all the time
        if (cnt >= ImMin(64u, prims)) {
            if (prims_culled >= cnt)
                prims_culled -= cnt; // reuse previous reservation
            else {
                // add more elements to previous reservation
                draw_list.PrimReserve((cnt - prims_culled) * renderer.IdxConsumed, (cnt - prims_culled) * renderer.VtxConsumed);
                prims_culled = 0;
            }
        }
        else
        {
            if (prims_culled > 0) {
                draw_list.PrimUnreserve(prims_culled * renderer.IdxConsumed, prims_culled * renderer.VtxConsumed);
                prims_culled = 0;
            }
            cnt = ImMin(prims, (MaxIdx<ImDrawIdx>::Value - 0/*draw_list._VtxCurrentIdx*/) / renderer.VtxConsumed);
            // reserve new draw command
            draw_list.PrimReserve(cnt * renderer.IdxConsumed, cnt * renderer.VtxConsumed);
        }
        prims -= cnt;
        for (unsigned int ie = idx + cnt; idx != ie; ++idx) {
            if (!renderer.Render(draw_list, cull_rect, idx))
                prims_culled++;
        }
    }
    if (prims_culled > 0)
        draw_list.PrimUnreserve(prims_culled * renderer.IdxConsumed, prims_culled * renderer.VtxConsumed);
}

template <template <class> class _Renderer, class _Getter, typename ...Args>
void RenderPrimitives1(const _Getter& getter, Args... args) {