Method SetCurrentChannel

src/imgui/imgui_draw.cpp:2220–2242

}

void ImDrawListSplitter::SetCurrentChannel(ImDrawList* draw_list, int idx)
{
    IM_ASSERT(idx >= 0 && idx < _Count);
    if (_Current == idx)
        return;

    // Overwrite ImVector (12/16 bytes), four times. This is merely a silly optimization instead of doing .swap()
    memcpy(&_Channels.Data[_Current]._CmdBuffer, &draw_list->CmdBuffer, sizeof(draw_list->CmdBuffer));
    memcpy(&_Channels.Data[_Current]._IdxBuffer, &draw_list->IdxBuffer, sizeof(draw_list->IdxBuffer));
    _Current = idx;
    memcpy(&draw_list->CmdBuffer, &_Channels.Data[idx]._CmdBuffer, sizeof(draw_list->CmdBuffer));
    memcpy(&draw_list->IdxBuffer, &_Channels.Data[idx]._IdxBuffer, sizeof(draw_list->IdxBuffer));
    draw_list->_IdxWritePtr = draw_list->IdxBuffer.Data + draw_list->IdxBuffer.Size;

    // If current command is used with different settings we need to add a new command
    ImDrawCmd* curr_cmd = (draw_list->CmdBuffer.Size == 0) ? NULL : &draw_list->CmdBuffer.Data[draw_list->CmdBuffer.Size - 1];
    if (curr_cmd == NULL)
        draw_list->AddDrawCmd();
    else if (curr_cmd->ElemCount == 0)
        ImDrawCmd_HeaderCopy(curr_cmd, &draw_list->_CmdHeader); // Copy ClipRect, TexRef, VtxOffset
    else if (ImDrawCmd_HeaderCompare(curr_cmd, &draw_list->_CmdHeader) != 0)
        draw_list->AddDrawCmd();
}

//-----------------------------------------------------------------------------
// [SECTION] ImDrawData