Command_buffer_recording

    //object picking;
    if (settings.pick) {
        //start recording object picking command buffer
        if (vkBeginCommandBuffer(object_picking_commandBuffer[image_index], &beginInfo) != VK_SUCCESS) {
            throw std::runtime_error("failed to begin recording command buffer!");
        }
        //begin renderpass
        VkRenderPassBeginInfo object_picking_renderpass_begin_info{};
        object_picking_renderpass_begin_info.sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;
        object_picking_renderpass_begin_info.renderPass = object_picking_pass;
        object_picking_renderpass_begin_info.framebuffer = object_picking_fb;
        object_picking_renderpass_begin_info.renderArea.offset = { 0,0 };
        object_picking_renderpass_begin_info.renderArea.extent = swapChainExtent;
        object_picking_renderpass_begin_info.clearValueCount = static_cast<uint32_t>(clearValues.size());
        object_picking_renderpass_begin_info.pClearValues = clearValues.data();

        vkCmdBeginRenderPass(object_picking_commandBuffer[image_index], &object_picking_renderpass_begin_info,
                             VK_SUBPASS_CONTENTS_INLINE);

        vkCmdBindPipeline(object_picking_commandBuffer[image_index], VK_PIPELINE_BIND_POINT_GRAPHICS,
                          pipelines[object_picking_pipeline].pipeline);

        //render all renderables
        for (size_t j = 0; j < active_renderables.size(); j++)
        {
            //the dynamic pipeline state means we have to set the scissor before each draw
            VkRect2D rect{};
            rect.offset.x = InputSystem::get_mouse_position().x > 0 ? InputSystem::get_mouse_position().x : 0;
            rect.offset.y = InputSystem::get_mouse_position().y > 0 ? InputSystem::get_mouse_position().y : 0;
            rect.extent = { 1,1 };

            //can only be used with a dynamic scissor state
            vkCmdSetScissor(object_picking_commandBuffer[image_index], 0, 1, &rect);

            //bind descriptor sets for current object
            vkCmdBindDescriptorSets(commandBuffers[image_index], VK_PIPELINE_BIND_POINT_GRAPHICS,
                                    pipelines[object_picking_pipeline].pipeline_layout, 0, 1,/*choose correct descriptor*/,
                                    0,nullptr);

            //bind vertex and index buffers for current object
            vkCmdBindVertexBuffers(commandBuffers[image_index], 0, 1,
                                   &vkvertexBuffers[renderables[active_renderables[j]].vertex_buffer_index], &vertexOffsets[j]);
            vkCmdBindIndexBuffer(commandBuffers[image_index], vkindexBuffers[renderables[active_renderables[j]].index_buffer_index],
                                 0,VK_INDEX_TYPE_UINT32);

            //draw
            vkCmdDrawIndexed(object_picking_commandBuffer[image_index], static_cast<uint32_t>(index_size), 1, 0, 0, 0);

            offset += index_size[j];
       }
        vkCmdEndRenderPass(object_picking_commandBuffer[image_index]);

        if (vkEndCommandBuffer(object_picking_commandBuffer[image_index]) != VK_SUCCESS) {
            throw std::runtime_error("failed to record command buffer!");
        }


    }