saveSwatchesCmd.cpp

//-
// ==========================================================================
// Copyright 2015 Autodesk, Inc.  All rights reserved.
//
// Use of this software is subject to the terms of the Autodesk
// license agreement provided at the time of installation or download,
// or which otherwise accompanies this software in either electronic
// or hard copy form.
// ==========================================================================
//+

//  This plugin provides the 'saveSwatches' command which takes a list of
//  render nodes and saves out their swatches as 64x64 PNG images.
//
//  The plugin demonstrates the following:
//
//  - how to find a Maya control's QWidget from its name
//  - how to grab a snapshot of a control and save it to an image file

//  Must ensure that at least one Qt header is included before anything
//  else.
#include <QtGui/QPixmap>
#include <QtCore/QString>
#include <QtWidgets/QWidget>

#include <maya/MArgList.h>
#include <maya/MFnPlugin.h>
#include <maya/MGlobal.h>
#include <maya/MQtUtil.h>
#include <maya/MString.h>

#include <saveSwatchesCmd.h>

const MString  SaveSwatchesCmd::commandName("saveSwatches");


MStatus SaveSwatchesCmd::doIt(const MArgList& args)
{
    //  If we weren't passed any arguments, display a help string.
    if (args.length() == 0) {
        MGlobal::displayError(
            MString("Usage: ")
            + SaveSwatchesCmd::commandName
            + " renderNode [renderNode ...]"
        );
        return MS::kInvalidParameter;
    }

    //  Create a window with a swatchDisplayPort in it.
    MString swatchPortName = MGlobal::executeCommandStringResult(
        "window -h 64 -w 64 swatchGrabber;"
        "rowLayout -nc 1;"
        "string $swatchPort = `swatchDisplayPort -w 64 -h 64 -rs 64`;"
        "showWindow;"
        "$swatchPort = $swatchPort;"
    );

    //  Find the swatchDisplayPort's QWidget.
    QWidget*  swatchPort = MQtUtil::findControl(swatchPortName);

    if (swatchPort) {
        //  Step through each render node and take its snapshot.
        for (unsigned int i = 0; i < args.length(); ++i) {
            MString renderNode = args.asString(i);

            //  Assign the material node to the swatchDisplayPort which
            //  will automatically render its swatch.
            MGlobal::executeCommand(
                MString("swatchDisplayPort -e -sn ") + renderNode + " " + swatchPortName
            );

            //  Swatch rendering takes place during idle events, so let's
            //  give it a chance to run.
            MGlobal::executeCommand("flushIdleQueue");

            //  Take a snapshot of the widget.
            QPixmap swatch = QPixmap::grabWidget(swatchPort);

            //  Save the snapshot as a PNG file.
            QString fileName = renderNode.asChar();
            fileName += ".png";
            swatch.save(fileName, "png", 100);
        }
    } else {
        MGlobal::displayError(
            MString("Could not find swatchDisplayPort '") + swatchPortName + "'"
        );
        return MS::kFailure;
    }

    //  Get rid of the window.
    MGlobal::executeCommand("deleteUI swatchGrabber");

    return MS::kSuccess;
}


// ==========================================================================
//
//          Plugin load/unload
//
// ==========================================================================

MStatus initializePlugin(MObject plugin)
{
    MStatus     st;
    MFnPlugin   pluginFn(plugin, "Autodesk, Inc.", "1.0", "Any", &st);

    if (!st) {
        MGlobal::displayError(
            MString("saveSwatchesCmd - could not initialize plugin: ")
            + st.errorString()
        );
        return st;
    }

    //  Register the command.
    st = pluginFn.registerCommand(SaveSwatchesCmd::commandName, SaveSwatchesCmd::creator);

    if (!st) {
        MGlobal::displayError(
            MString("saveSwatchesCmd - could not register '")
            + SaveSwatchesCmd::commandName + "' command: "
            + st.errorString()
        );
        return st;
    }

    return st;
}


MStatus uninitializePlugin(MObject plugin)
{
    MStatus     st;
    MFnPlugin   pluginFn(plugin, "Autodesk, Inc.", "1.0", "Any", &st);

    if (!st) {
        MGlobal::displayError(
            MString("saveSwatchesCmd - could not uninitialize plugin: ")
            + st.errorString()
        );
        return st;
    }

    //  Deregister the command.
    st = pluginFn.deregisterCommand(SaveSwatchesCmd::commandName);

    if (!st) {
        MGlobal::displayError(
            MString("saveSwatchesCmd - could not deregister '")
            + SaveSwatchesCmd::commandName + "' command: "
            + st.errorString()
        );
        return st;
    }

    return st;
}