Pipeline Configuration

/**
 * Base class for other pipeline classes.
 * Methods in this class are reserved for internal use.
 */
abstract class PacketPipeline {
    /** Default constructor */
    PacketPipeline();
    
    /** Get RGB packet parser for color data processing */
    DataCallback getRgbPacketParser();
    
    /** Get IR packet parser for depth/IR data processing */
    DataCallback getIrPacketParser();
    
    /** Get RGB packet processor instance */
    RgbPacketProcessor getRgbPacketProcessor();
    
    /** Get depth packet processor instance */
    DepthPacketProcessor getDepthPacketProcessor();
}

/**
 * Pipeline with CPU depth processing.
 * Most compatible option but may be slower than GPU-accelerated pipelines.
 */
class CpuPacketPipeline extends PacketPipeline {
    /** Default constructor for CPU-only processing */
    CpuPacketPipeline();
}

// Create CPU pipeline for maximum compatibility
PacketPipeline pipeline = new CpuPacketPipeline();

// Open device with CPU pipeline
Freenect2Device device = freenect2.openDevice(serial, pipeline);

// CPU pipeline is automatically managed - no additional configuration needed
if (device != null) {
    System.out.println("Device opened with CPU pipeline");
    device.start();
}

/**
 * Pipeline with OpenGL depth processing.
 * Requires OpenGL support and may provide better performance than CPU pipeline.
 */
class OpenGLPacketPipeline extends PacketPipeline {
    /** Default constructor for OpenGL processing */
    OpenGLPacketPipeline();
    
    /** 
     * Constructor with OpenGL context and debug options
     * @param parent_opengl_context Existing OpenGL context to share (or null)
     * @param debug Enable debug output for troubleshooting
     */
    OpenGLPacketPipeline(Pointer parent_opengl_context, @Cast("bool") boolean debug);
}

// Create OpenGL pipeline with default settings
PacketPipeline pipeline = new OpenGLPacketPipeline();

// Create OpenGL pipeline with debug enabled
PacketPipeline debugPipeline = new OpenGLPacketPipeline(null, true);

// Open device with OpenGL pipeline
try {
    Freenect2Device device = freenect2.openDevice(serial, pipeline);
    if (device != null) {
        System.out.println("Device opened with OpenGL pipeline");
        device.start();
    }
} catch (Exception e) {
    System.err.println("OpenGL pipeline failed, falling back to CPU");
    PacketPipeline cpuPipeline = new CpuPacketPipeline();
    Freenect2Device device = freenect2.openDevice(serial, cpuPipeline);
}

/**
 * Pipeline that dumps packets for debugging purposes.
 * Useful for analyzing raw sensor data and troubleshooting issues.
 * Provides access to internal depth processing tables.
 */
class DumpPacketPipeline extends PacketPipeline {
    /** Constructor for dump pipeline */
    DumpPacketPipeline();
    
    /** Get depth P0 tables required for depth decoding */
    @Cast("const unsigned char*") BytePointer getDepthP0Tables(@Cast("size_t*") SizeTPointer length);
    
    /** Get depth X lookup table */
    @Const FloatPointer getDepthXTable(@Cast("size_t*") SizeTPointer length);
    
    /** Get depth Z lookup table */
    @Const FloatPointer getDepthZTable(@Cast("size_t*") SizeTPointer length);
    
    /** Get depth value lookup table */
    @Const ShortPointer getDepthLookupTable(@Cast("size_t*") SizeTPointer length);
}

/**
 * Callback interface for packet data processing
 */
abstract class DataCallback {
    // Implementation varies by packet type
}

/**
 * RGB packet processor for color frame data
 */
abstract class RgbPacketProcessor {
    // Processes color sensor packets into RGB frames
}

/**
 * Depth packet processor for depth/IR frame data  
 */
abstract class DepthPacketProcessor {
    // Processes ToF sensor packets into depth and IR frames
}

/**
 * Container for packet pipeline components
 */
class PacketPipelineComponents {
    // Aggregates processing components
}

// Pipeline performance comparison example
long startTime, endTime;

// Test CPU pipeline
PacketPipeline cpuPipeline = new CpuPacketPipeline();
Freenect2Device device = freenect2.openDevice(serial, cpuPipeline);
device.start();

startTime = System.currentTimeMillis();
// Capture 10 frames for timing
for (int i = 0; i < 10; i++) {
    if (listener.waitForNewFrame(frames, 1000)) {
        listener.release(frames);
    }
}
endTime = System.currentTimeMillis();
long cpuTime = endTime - startTime;

device.stop();
device._close();

// Test OpenGL pipeline
PacketPipeline glPipeline = new OpenGLPacketPipeline();
device = freenect2.openDevice(serial, glPipeline);
device.start();

startTime = System.currentTimeMillis();
// Capture same 10 frames
for (int i = 0; i < 10; i++) {
    if (listener.waitForNewFrame(frames, 1000)) {
        listener.release(frames);
    }
}
endTime = System.currentTimeMillis();
long glTime = endTime - startTime;

System.out.println("CPU Pipeline: " + cpuTime + "ms");
System.out.println("OpenGL Pipeline: " + glTime + "ms");
System.out.println("Performance gain: " + (cpuTime / (float)glTime) + "x");

/**
 * Robust pipeline selection with fallback support
 */
public static Freenect2Device openDeviceWithBestPipeline(
        Freenect2 freenect2, String serial) {
    
    // Try pipelines in order of preference
    PacketPipeline[] pipelines = {
        new OpenGLPacketPipeline(),  // Best performance
        new CpuPacketPipeline()      // Fallback compatibility
    };
    
    String[] pipelineNames = {"OpenGL", "CPU"};
    
    for (int i = 0; i < pipelines.length; i++) {
        try {
            Freenect2Device device = freenect2.openDevice(serial, pipelines[i]);
            if (device != null) {
                System.out.println("Successfully opened device with " + 
                                 pipelineNames[i] + " pipeline");
                return device;
            }
        } catch (Exception e) {
            System.err.println(pipelineNames[i] + " pipeline failed: " + 
                             e.getMessage());
            if (i == pipelines.length - 1) {
                System.err.println("All pipelines failed!");
                return null;
            }
        }
    }
    
    return null;
}

public class PipelineManager {
    private Freenect2 freenect2;
    private Freenect2Device device;
    private PacketPipeline currentPipeline;
    
    public boolean initializeWithPipeline(String pipelineType) {
        try {
            // Create pipeline based on type
            switch (pipelineType.toLowerCase()) {
                case "cpu":
                    currentPipeline = new CpuPacketPipeline();
                    break;
                case "opengl":
                    currentPipeline = new OpenGLPacketPipeline();
                    break;
                case "debug":
                    currentPipeline = new DumpPacketPipeline();
                    break;
                default:
                    throw new IllegalArgumentException("Unknown pipeline: " + pipelineType);
            }
            
            // Open device with selected pipeline
            String serial = freenect2.getDefaultDeviceSerialNumber().getString();
            device = freenect2.openDevice(serial, currentPipeline);
            
            if (device == null) {
                System.err.println("Failed to open device with " + pipelineType + " pipeline");
                return false;
            }
            
            System.out.println("Initialized with " + pipelineType + " pipeline");
            return true;
            
        } catch (Exception e) {
            System.err.println("Pipeline initialization failed: " + e.getMessage());
            return false;
        }
    }
    
    public void cleanup() {
        if (device != null) {
            device.stop();
            device._close();
            device = null;
        }
        currentPipeline = null;
    }
}