Toggle the GUI visualization of light frustrums / green lines

[osrf-migration]

Original report (archived issue) by Andrew Symington (Bitbucket: asymingt).

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I would like to be able to turn off the visualization of lights in the GUI, as I have a green laser plugin for my model that looks confusingly like the lines used to visualize all directional/spot lights! The method would be similar to the <visualize> child of <sensor> in SDF.

Perhaps something along these lines:

<light type="...">
  <visualize>false</visualize>
  ...
</light>

In addition, since one cannot attach a VisualPlugin to a light visual, it would be extremely useful to set visibility flags in the msgs::Light, so that one can programatically create / update light visibility.

[osrf-migration]

Original comment by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).

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We already have ways to toggle visualization of the Grid, Origin, Contacts, Link Frames, Joints, etc. I think we could add this for lights as well.

[osrf-migration]

Original comment by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).

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• changed component from "rendering" to "gui"

[osrf-migration]

Original comment by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).

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We added Link Frame visualizations to the GUI in pull request #1762, which may provide an example for some of the changes to be made, for example adding a new bool to ScenePrivate.hh for showLights. Since the visual already exists, it should be easier to solve this problem, just adding the enable/disable visualization logic.

[osrf-migration]

Original comment by Ian Chen (Bitbucket: Ian Chen, GitHub: iche033).

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Issue #2508 was marked as a duplicate of this issue.

[osrf-migration]

Original comment by Ian Chen (Bitbucket: Ian Chen, GitHub: iche033).

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pull request #3011

[shonigmann]

With #3011, is there anything exposed to the end user to toggle light visualization (e.g. from the CLI, GUI or within URDF)? Thanks!

[iche033]

not that I know of. In the end, we wrote a plugin that loops through the lights in the scene and call ShowVisual(false) to turn them off.

[len0rd]

@iche033 Would you be able to point me to this plugin you wrote that disables the light visual? I'm attempting to do something similar. Thanks!

[iche033]

looks like that particular branch with the plugin was lost when migrating a repo from bitbucket to github. So I'll just post the code here. I took out some include headers related to other projects so there maybe additional gazebo headers you'll need to add to the code to build it.

LightVisualPlugin.cc

/*
 * Copyright (C) 2018 Open Source Robotics Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
*/

#include <map>

#include <gazebo/common/Assert.hh>
#include <gazebo/common/Events.hh>

#include "LightVisualPlugin.hh"

namespace gazebo
{
  /// \internal
  /// \brief Private data for the Light class
  class LightVisualPluginPrivate
  {
    /// \brief Map of light names to visualize flag
    public: std::map<std::string, bool> lights;

    /// \brief PreRender connection
    public: event::ConnectionPtr preRenderCon;

    /// \brief PreRender connection
    public: rendering::ScenePtr scene;
  };
}


using namespace gazebo;

GZ_REGISTER_VISUAL_PLUGIN(LightVisualPlugin)

/////////////////////////////////////////////////
LightVisualPlugin::LightVisualPlugin()
  : dataPtr(new LightVisualPluginPrivate)
{
}

/////////////////////////////////////////////////
void LightVisualPlugin::Load(rendering::VisualPtr _parent, sdf::ElementPtr _sdf)
{
  GZ_ASSERT(_parent, "LightVisualPlugin parent pointer is NULL");

  this->dataPtr->scene = _parent->GetScene();
  rendering::VisualPtr linkVis = _parent->GetParent();

  if (_sdf->HasElement("light"))
  {
    auto sdfLight = _sdf->GetElement("light");
    while (sdfLight)
    {
      if (sdfLight->HasElement("id") && sdfLight->HasElement("visualize"))
      {
        std::string lightId = sdfLight->Get<std::string>("id");

        size_t pos = 0;
        while ((pos = lightId.find("/", pos)) != std::string::npos)
        {
          lightId = lightId.replace(pos, 1, "::");
          pos += 2;
        }

        bool visualize = sdfLight->Get<bool>("visualize");
        std::string lightName = linkVis->Name() + "::" + lightId;
        this->dataPtr->lights[lightName] = visualize;
      }

      sdfLight = sdfLight->GetNextElement("light");
    }
  }

  if (!this->dataPtr->lights.empty())
  {
    this->dataPtr->preRenderCon =
        event::Events::ConnectPreRender(
        std::bind(&LightVisualPlugin::PreRender, this));
  }
}

/////////////////////////////////////////////////
void LightVisualPlugin::PreRender()
{
  for (auto lightIt = this->dataPtr->lights.begin();
      lightIt != this->dataPtr->lights.end();)
  {
    rendering::LightPtr light =
        this->dataPtr->scene->LightByName(lightIt->first);
    if (light)
    {
      light->ShowVisual(lightIt->second);
      this->dataPtr->lights.erase(lightIt++);
    }
    else
    {
      ++lightIt;
    }
  }

  if (this->dataPtr->lights.empty())
  {
    this->dataPtr->preRenderCon.reset();
    return;
  }
}

LightVisualPlugin.hh

/*
 * Copyright (C) 2018 Open Source Robotics Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
*/
#ifndef GAZEBO_LIGHTVISUALPLUGIN_HH_
#define GAZEBO_LIGHTVISUALPLUGIN_HH_

#include <memory>

#include <gazebo/rendering/rendering.hh>
#include <gazebo/common/Plugin.hh>
#include <sdf/sdf.hh>

namespace gazebo
{
  // forward declaration
  class LightVisualPluginPrivate;

  /// \brief A plugin that toggles light visuals
  class LightVisualPlugin : public VisualPlugin
  {
    /// \brief Constructor
    public: LightVisualPlugin();

    // Documentation inherited
    public: virtual void Load(rendering::VisualPtr _parent,
        sdf::ElementPtr _sdf);

    /// \brief PreRender event callback
    public: virtual void PreRender();

    /// \internal
    /// \brief Pointer to private data
    private: std::unique_ptr<LightVisualPluginPrivate> dataPtr;
  };
}
#endif

If I remember correctly, the usage is:

<plugin ....>
  <light>
    <id>some_light_name</id> 
    <visualize>false</visualize>
  </light>
  <light>
    ...
  </light>
</plugin>