You cannot assign shortcuts to buttons.
An alternative solution (which I have used in the past) is to create a CommandData plugin for each button, and let the CommandData::Execute call the button. Or instead of a CommandData plugin you could also create a separate script for each button.
Either way, these can then be assigned a shortcut.

If I remember correctly we did discuss the other way (from CommandData to ToolData) quite a while ago (see https://plugincafe.maxon.net/topic/10044/13513_using-objectmessage). But I guess using this same technique could still be applicable to your current request.

Most important is to understand that a CoreMessage is not captured by a ToolData. This type of message can only be captured by a MessageData plugin, where you then could "translate" it into a message that actually is sent to the ToolData.

What I have been successful in using is, performing following from the "transmitter":

BasePlugin* tool = FindPlugin(TOOL_PLUGIN_ID, PLUGINTYPE::TOOL);
if (tool)
	tool->Message(TOOL_MSG_PREPAREDATA);

Where TOOL_PLUGIN_ID is the plugin ID of the ToolData, and TOOL_MSG_PREPAREDATA is a custom defined message, using a unique plugin ID.

And then using following in the "receiver" ToolData:

Bool MyToolData::Message(BaseDocument *doc, BaseContainer &data, Int32 type, void *t_data)
{
	if (type == TOOL_MSG_PREPAREDATA)
	{
		PrepareData();
	}

	return DescriptionToolData::Message(doc, data, type, t_data);
}

@bentraje said in Bug on GetActiveObjects() on R20.057?:

objSel = doc.GetActiveObjects(c4d.GETACTIVEOBJECTFLAGS_SELECTIONORDER)
print objSel[0]
print objSel[1]

Works fine by me.

I have a cube and a plane primitive. With the two selected, I get a printout for both. No out of range.
Running 20.057 (on Windows).

<c4d.BaseObject object called 'Plane/Plane' with ID 5168 at 0x0000004C44847570>
<c4d.BaseObject object called 'Cube/Cube' with ID 5159 at 0x0000004C448476D0>

When I only select a single object then I get an out of range (obviously):

IndexError: list index out of range

EDIT:
Hang on, when I make one the child of the other and have both selected, I do get an out of range.
But this is obvious, since your active objects flag doesn't mention children. As such, you do only have a single parent object selected.

To take children into account as being detected as selected, you need:

 objSel = doc.GetActiveObjects(c4d.GETACTIVEOBJECTFLAGS_SELECTIONORDER | c4d.GETACTIVEOBJECTFLAGS_CHILDREN )

spam frenzy all over again, lately.

I have been in need of something similar as well. And if I remember correctly it has been discussed a few years ago.
Reason is that a ToolData or DescriptionToolData might need to initialize some stuff depending the currently active object. When the user selects a different object in the ObjectManager, the ToolData might need to reinitialize some stuff.

The solution proposed in the past was to use a MessageData and listen to EVMSG_CHANGE to check if a different object has been selected using the object's "unique" id and then trigger the ToolData by sending a SpecialEvent ... or something.

It is quite a complex implementation that seems to work, but probably is very error prone.
I wish we would have had some kind of message telling the active object selection was changed (from inside the ToolData), not via-via. And definitely not using such a hacky and complex solution.
It has been a while, but I seem to remember that the whole use of the object's unique id was rather flawed as the id didn't exactly seem to be that unique after all.

Anyway, I am still hoping for a nice solution to detect when user changes the current active object. But it seems to not be possible after all.

I am less active since a few months, and this will probably not change any time soon, but let that not restrict me for sending Best Wishes for 2021 to everyone of the SDK team.
Not only to those more present and visible in the forums, but also to those behind the scenes that keep everything running.

Thank you for your 2020 support and best wishes for 2021.

You need to obtain the tool's data in order to be able to modify/set it.
The callcommand just activates the tool.

import c4d

def main():

    # activate the command
    c4d.CallCommand(1019952)

    # change its settings
    nTool = c4d.plugins.GetToolData(doc, 1019952)
    nTool[c4d.ID_CA_JOINT_NAMING_REPLACE] = "_L_"
    nTool[c4d.ID_CA_JOINT_NAMING_REPLACE_WITH] = "_R_"

# Execute main()
if __name__=='__main__':
    main()

In the above code "nTool" is a BaseContainer, that won't work.

I also found the following in the legacy forum

import c4d

def main():
    
    toolID = 1019952
    c4d.CallCommand(toolID) 

    tool=c4d.plugins.FindPlugin(toolID, c4d.PLUGINTYPE_TOOL)  
    tool[c4d.ID_CA_JOINT_NAMING_REPLACE] = "_L_" 
    tool[c4d.ID_CA_JOINT_NAMING_REPLACE_WITH]= "_R_"
    c4d.CallButton(tool, c4d.ID_CA_JOINT_NAMING_REPLACE_APPLY)  
    
    c4d.EventAdd()

Another take on modifying the settings, since the "tool" returned from FindPlugin is a BasePlugin which is derived from BaseList2D, exactly what we need for the CallButton

The geometry of an object is stored in hidden tags (points and polygons, namely)
These are not visible, nor selectable ... and thus can theoretically not be deleted by user. But you still can access these via Python, or C++. As such, when removing all tags you also remove critical ones, that are needed by the object in order to exist.

import c4d

def main():
    c4d.gui.ActiveObjectManager_SetObject(c4d.ACTIVEOBJECTMODE_OBJECT, op, 0, c4d.ACTIVEOBJECTMANAGER_SETOBJECTS_OPEN)

if __name__=='__main__':
    main()

You create a custom GUI to display your custom data by deriving a class from iCustomGUI

class iMyCustomGUI : public iCustomGui
...

Then in you CustomGUIData derived class you implement the allocation by providing the derived iCustomGUI

CDialog* ReferencePointCustomGUI::Alloc(const BaseContainer& settings)
{
    iMyCustomGUI* dlg = NewObjClear(iMyCustomGUI, settings, GetPlugin());
    ...

you can find more details in the R20 SDK example customdata_customgui.cpp in folder cinema4dsdk\source\gui
Works OK for R16 upto at least R21 (I have not used/tested in more recent versions)

@césar-vonc

Yes you can do this with scripts. I have done this in the past with my Dials plugin.

Let's say you have a CommandData.
You simply create a script which does perform c4d.CallCommand(pluginID, option)
where <pluginID> is the plugin id of the CommandData, and option is the CallCommand::ExecuteSubID to be executed.

You then assign a shortcut / icon to your script ... and you're done.
You can create as many scripts / shortcuts as you want, each with a different <option> value

@m_magalhaes

Did some more testing, using the original code and the conversion code, with linear workflow on and off.

When I look at the original code with linear workflow OFF, this most resembles the gradient from Photoshop. Except for the gap at the top .. obviously.

The result from conversion code with linear workflow ON is what I am using now, as this provides the smallest gap. And to my eyes that result looks the most linear.

@m_magalhaes
Thanks for the tip to convert the alpha to linear value.
It is not perfect, but it does reduce the "gap" to a much smaller percentage.

With the original value I have a gap of 19%. Any alpha value below 20% opacity is just drawn as full transparent.
With the alpha value converted to linear this is now reduced to a gap of only 2%
I can live with this limitation.

It would be nice to hear from devs if there is a workaround to get a full gradient.
But I am already setting this topic as "solved".

I am trying to draw onto the viewport with some alpha values but don't get the expected value.
To test out I simply draw a white rectangle as background and on top of that I draw a black line with a varying alpha value. Basically building a gradient going from full transparency (top) to full opaque (bottom).

To compare to what would be expected I've drawn a Photoshop gradient at the right.
To me it seems the first N lines are not drawn at all, or their alpha value prevent the lines from being visible, while the rest of the "gradient" doesn't seem to be linear.

Main code of the "gradient"

for (Int32 i = 0; i <= 255; ++i)
{
	clipMap->SetColor(0, 0, 0, i);
	clipMap->Line(10, 10+i, width-10, 10+i);
}

This is the result with R20, but similar results obtained with R21. Have not tested more recent releases.

Am I missing something about the "gradient" implementation, or is there another setting missing?

Here's the full plugin implementation:

// ========================
// Cinema 4D C++ plugin
//
// PluginName: Test
// Dummy "empty" plugin
// ========================

// Main.cpp

#include "c4d.h"
#include "lib_clipmap.h"

// Dummy IDs - for demonstration purposes only
#define MYSCENEHOOK_PLUGIN_ID	1000000




Bool DrawTheStuff(BaseDraw *bd, Int32 x, Int32 y)
{
	AutoAlloc<GeClipMap> clipMap;
	if (!clipMap) return false;

	Int32 width = 300;
	Int32 height = 275;

	// now the dimensions are known
	// intialize clipmap for the actual drawing
	if (clipMap->Init(width, height, 32) != IMAGERESULT::OK)
		return false;
	clipMap->BeginDraw();
	// fill background with white
	clipMap->SetColor(255, 255, 255, 255);
	clipMap->FillRect(0, 0, width, height);

	// draw black stripes over background with different alpha values,
	// leaving a border of 10 pixels of background at each side
	for (Int32 i = 0; i <= 255; ++i)
	{
		clipMap->SetColor(0, 0, 0, i);
		clipMap->Line(10, 10+i, width-10, 10+i);
	}

	clipMap->EndDraw();
	const BaseBitmap* bitmap = clipMap->GetBitmap();
	if (bitmap)
	{
		maxon::Vector *positions;
		iferr(positions = NewMem(maxon::Vector, 4))
			return false;
		maxon::Vector *colors = nullptr; // NewMem(maxon::Vector, 4);
		maxon::Vector *normals = nullptr; // NewMem(maxon::Vector, 4);
		maxon::Vector *uvcoords;
		iferr(uvcoords = NewMem(maxon::Vector, 4))
		{
			DeleteMem(positions);
			return false;
		}

		// center image on top of the point
		x -= (width / 2);
		y -= (height / 2);

		positions[0] = maxon::Vector(x, y, 0);
		positions[1] = maxon::Vector(x + width, y, 0);
		positions[2] = maxon::Vector(x + width, y + height, 0);
		positions[3] = maxon::Vector(x, y + height, 0);

		uvcoords[0] = maxon::Vector(0, 0, 0);
		uvcoords[1] = maxon::Vector(1, 0, 0);
		uvcoords[2] = maxon::Vector(1, 1, 0);
		uvcoords[3] = maxon::Vector(0, 1, 0);

		// draw texture in screen space
		const Matrix currentMg = bd->GetMg();
		bd->SetMatrix_Screen();
		bd->SetLightList(BDRAW_SETLIGHTLIST_NOLIGHTS);
		const DRAW_ALPHA        alpha = DRAW_ALPHA::NORMAL; //DRAW_ALPHA::NONE
#if API_VERSION < 23000
		const DRAW_TEXTUREFLAGS texture = DRAW_TEXTUREFLAGS::NONE;
#else
		const DRAW_TEXTUREFLAGS texture = DRAW_TEXTUREFLAGS::INTERPOLATION_NEAREST | DRAW_TEXTUREFLAGS::TEMPORARY;
#endif
		bd->DrawTexture(bitmap, positions, colors, normals, uvcoords, 4, alpha, texture);

		DeleteMem(positions);
		//DeleteMem(colors);
		//DeleteMem(normals);
		DeleteMem(uvcoords);

		// restore the matrix
		bd->SetMatrix_Matrix(nullptr, currentMg);
	}

	return true;
}


// ====================================
// SceneHook
// ====================================

class MySceneHook : public SceneHookData
{
	INSTANCEOF(MySceneHook, SceneHookData)

public:
	MySceneHook();
	virtual Bool Draw(BaseSceneHook *node, BaseDocument *doc, BaseDraw *bd, BaseDrawHelp *bh, BaseThread *bt, SCENEHOOKDRAW flags);

	static NodeData *Alloc(void) { return NewObjClear(MySceneHook); }
};

MySceneHook::MySceneHook() : SceneHookData()
{
}

Bool MySceneHook::Draw(BaseSceneHook *node, BaseDocument *doc, BaseDraw *bd, BaseDrawHelp *bh, BaseThread *bt, SCENEHOOKDRAW flags)
{
	if (!node || !doc || !bd || !bh)
		return false;
	if (flags != SCENEHOOKDRAW::DRAW_PASS)
		return true;

	Int32 lLeft, lTop, lRight, lBottom;
	bd->GetFrame(&lLeft, &lTop, &lRight, &lBottom);

	bd->SetMatrix_Screen();

	DrawTheStuff(bd, SAFEINT32((lLeft + lRight) * 0.5), SAFEINT32((lTop + lBottom) * 0.5));


	// restore basedraw matrix
	bd->SetMatrix_Matrix(nullptr, Matrix());

	return true;
}

// ====================================
// Plugin Main 
// ====================================
Bool PluginStart(void)
{
	ApplicationOutput("Test"_s);

	RegisterSceneHookPlugin(MYSCENEHOOK_PLUGIN_ID, "MySceneHook"_s, 0, MySceneHook::Alloc, EXECUTIONPRIORITY_GENERATOR, 0);

	return true;
}
void PluginEnd(void)
{
}
Bool PluginMessage(Int32 id, void * data)
{
	switch (id) {
	case C4DPL_INIT_SYS:
		if (!g_resource.Init())
			return false;
		return true;
	case C4DMSG_PRIORITY:
		return true;
	case C4DPL_BUILDMENU:
		break;
	case C4DPL_ENDACTIVITY:
		return true;
	}
	return false;
}

I am wondering why anyone would want to rewrite c4dsymbols and string files dynamically, as there are probably better solutions to handle what you are trying to achieve. Even if that requires a complete redesign of your plugin.

That said, you have PluginEnd() which is called when your plugin is unloaded
(see https://developers.maxon.net/docs/Cinema4DCPPSDK/html/page_manual_module_functions.html)
Or you could react to C4DPL_ENDPROGRAM or C4DPL_ENDACTIVITY, as mentioned in above link.

Not knowing what you're trying to achieve it's difficult to point you to a good solution, but I would suggest rethinking the whole concept of your plugin and avoid rewriting the files dynamically.

@ling said in interactions between two or more plugins which are in a single Python file:

I had changed my solution.

If you could share the solution, or at least the concept behind it, this might help others with a similar problem looking for a solution.

@Ling
You cannot simply call Message(the integer) on a CommandData.
As I mentioned in the link (https://plugincafe.maxon.net/topic/13379/send-message-to-commanddata) the CommandData expects a message of type MSG_COMMAND. You cannot pass any integer.

But since you want to send more information than just an integer you then cannot use the solution I provided by using the CommandData.ExecuteSubID.

Note that a CommandData is more like a "single-shot" action. It would probably be a better idea to look for something else to "change a value" than a CommandData.
Without knowing the whole idea behind your plugin it is hard to suggest something.

https://plugincafe.maxon.net/topic/11436/send-message-to-tooldata
https://plugincafe.maxon.net/topic/13379/send-message-to-commanddata

MSG_DOCUMENTINFO_TYPE_SAVE_BEFORE
-> Document is about to be written.
MSG_DOCUMENTINFO_TYPE_SAVE_AFTER
-> Document was saved.