Add OFX plugin support and related infrastructure

This commit extends the OFX plugin support in Olive by:

- Initializing and scanning for OFX plugins
- Updating PluginNode to handle OFX plugin parameters and inputs
- Adding necessary methods and properties for OFX plugin integration
- Enhancing NodeFactory to include OFX plugin nodes
- Refactoring and renaming OliveInstance to OlivePluginInstance
- Introducing new classes for parameter handling (ParamInstance)
- Adding PluginJob for rendering OFX plugins
- Adjusting CMakeLists.txt files to include new source files

app/pluginSupport/OlivePluginInstance.cpp

@@ -0,0 +1,169 @@
+/*
+ * Olive Community Edition - Non-Linear Video Editor
+ * Copyright (C) 2025 Olive CE Team
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "OlivePluginInstance.h"
+
+#include "OliveClip.h"
+#include "ofxCore.h"
+#include "ofxMessage.h"
+#include "common/Current.h"
+
+#include <cstdio>
+#include <QMessageBox>
+#include <qmessagebox.h>
+#include <qobject.h>
+#include <string.h>
+#include <QString>
+#include "paraminstance.h"
+namespace olive
+{
+namespace plugin
+{
+OfxStatus OlivePluginInstance::vmessage(const char *type, const char *id,
+								  const char *format, va_list args)
+{
+	char *buffer = new char[1024];
+
+	memset(buffer, 0, 1024 * sizeof(char));
+	vsprintf(buffer, format, args);
+
+	QString message(buffer);
+
+	delete[] buffer;
+
+	if (strncmp(type, kOfxMessageQuestion, strlen(kOfxMessageQuestion))) {
+		auto ret = QMessageBox::information(
+			nullptr, "", message, QMessageBox::Ok, QMessageBox::Cancel);
+
+		if (ret == QMessageBox::Ok) {
+			return kOfxStatReplyYes;
+		} else {
+			return kOfxStatReplyNo;
+		}
+
+	} else {
+		QMessageBox::information(nullptr, "", message);
+		return kOfxStatOK;
+	}
+}
+OfxStatus OlivePluginInstance::setPersistentMessage(const char *type, const char *id,
+											  const char *format, va_list args)
+{
+	char *buffer = new char[1024];
+
+	memset(buffer, 0, 1024 * sizeof(char));
+	int ret = vsprintf(buffer, format, args);
+	if (ret < 0) {
+		return kOfxStatFailed;
+	}
+	QString message(buffer);
+
+	delete[] buffer;
+
+	// If This is a error message
+	if (strncmp(type, kOfxMessageError, strlen(kOfxMessageError)) == 0) {
+		persistentErrors_.append({ ErrorType::Error, message });
+		QMessageBox::critical(nullptr, "", message);
+		// TODO: tell the shell to show the error
+	}
+	// A warning
+	else if (strncmp(type, kOfxMessageWarning, strlen(kOfxMessageError)) == 0) {
+		persistentErrors_.append({ ErrorType::Warning, message });
+		QMessageBox::warning(nullptr, "", message);
+		// TODO: tell the shell to show the warning
+
+	}
+	// A simple information
+	else if (strncmp(type, kOfxMessageMessage, strlen(kOfxMessageError)) == 0) {
+		persistentErrors_.append({ ErrorType::Message, message });
+		QMessageBox::information(nullptr, "", message);
+	} else {
+		return kOfxStatFailed;
+	}
+	return kOfxStatOK;
+}
+OfxStatus OlivePluginInstance::clearPersistentMessage()
+{
+	persistentErrors_.clear();
+	// TODO: tell the shell to remove message.
+	return kOfxStatOK;
+}
+void OlivePluginInstance::getProjectSize(double &xSize, double &ySize) const
+{
+	xSize =params_.width();
+	ySize =params_.height();
+}
+void OlivePluginInstance::getProjectOffset(double &xOffset, double &yOffset) const
+{
+	xOffset =params_.x();
+	yOffset =params_.y();
+}
+void OlivePluginInstance::getProjectExtent(double &xSize, double &ySize) const
+{
+	xSize =params_.width();
+	ySize =params_.height();
+	// TODO: Ensure this project does not support this.
+}
+double OlivePluginInstance::getProjectPixelAspectRatio() const
+{
+	return Current::getInstance()
+		.currentVideoParams()
+		.pixel_aspect_ratio()
+		.toDouble();
+}
+double OlivePluginInstance::getFrameRate() const
+{
+	return params_.frame_rate().toDouble();
+}
+
+double OlivePluginInstance::getEffectDuration() const
+{
+	// Return a default duration value
+	return 100.0;
+}
+
+double OlivePluginInstance::getFrameRecursive() const
+{
+	// Return current frame (this would typically be set by the host during rendering)
+	return 0.0;
+}
+
+void OlivePluginInstance::getRenderScaleRecursive(double &x, double &y) const
+{
+	// Return default render scale (1.0, 1.0)
+	x = 1.0;
+	y = 1.0;
+}
+OFX::Host::Param::Instance *
+OlivePluginInstance::newParam(const std::string &name,
+						OFX::Host::Param::Descriptor &Descriptor)
+{
+
+}
+
+OFX::Host::ImageEffect::ClipInstance *OlivePluginInstance::newClipInstance(
+	OFX::Host::ImageEffect::Instance *plugin,
+	OFX::Host::ImageEffect::ClipDescriptor *descriptor,
+	int index)
+{
+	// Create a new clip instance
+	OFX::Host::ImageEffect::ClipInstance* clipInstance = new OliveClipInstance(plugin, *descriptor, params_);
+	return clipInstance;
+}
+
+}
+}