Add getPropertyLimits to retrieve property limits

Author: doblon8

src/main/java/io/github/doblon8/openpnp/capture/CaptureProperty.java

@@ -0,0 +1,29 @@
+package io.github.doblon8.openpnp.capture;
+
+public enum CaptureProperty
+{
+    EXPOSURE(1),
+    FOCUS(2),
+    ZOOM(3),
+    WHITE_BALANCE(4),
+    GAIN(5),
+    BRIGHTNESS(6),
+    CONTRAST(7),
+    SATURATION(8),
+    GAMMA(9),
+    HUE(10),
+    SHARPNESS(11),
+    BACK_LIGHT_COMPENSATION(12),
+    POWER_LINE_FREQUENCY(13),
+    LAST(14),
+    ;
+
+    private final int value;
+    CaptureProperty(int value) {
+        this.value = value;
+    }
+
+    public int value() {
+        return value;
+    }
+}

src/main/java/io/github/doblon8/openpnp/capture/CaptureStream.java

@@ -73,6 +73,34 @@ public int getStreamFrameCount() {
         return Cap_getStreamFrameCount(context.getSegment(), id);
     }
 
+    /**
+     * Get the min/max limits and the default value of a camera/stream property (e.g. zoom, exposure etc.).
+     *
+     * @param property the property to get the limits for.
+     * @return a PropertyLimits object containing the min/max limits and the default value of the property.
+     * @throws CaptureException if an error occurs while getting the property limits.
+     */
+    public PropertyLimits getPropertyLimits(CaptureProperty property) {
+        try (Arena arena = Arena.ofConfined()) {
+            MemorySegment minPointer = arena.allocate(ValueLayout.JAVA_INT);
+            MemorySegment maxPointer = arena.allocate(ValueLayout.JAVA_INT);
+            MemorySegment defaultValuePointer = arena.allocate(ValueLayout.JAVA_INT);
+
+            int result = Cap_getPropertyLimits(context.getSegment(), id, property.value(), minPointer, maxPointer, defaultValuePointer);
+            CaptureResult captureResult = CaptureResult.values()[result];
+            return switch (captureResult) {
+                case OK -> new PropertyLimits(
+                        minPointer.get(ValueLayout.JAVA_INT, 0),
+                        maxPointer.get(ValueLayout.JAVA_INT, 0),
+                        defaultValuePointer.get(ValueLayout.JAVA_INT, 0)
+                );
+                case PROPERTY_NOT_SUPPORTED ->
+                        throw new CaptureException("Property " + property + " is not supported by this stream.");
+                default -> throw new CaptureException("Error getting property limit for property " + property + ": context, stream are invalid.");
+            };
+        }
+    }
+
     /**
      * Check if a stream is open, i.e. is capturing data.
      *

src/main/java/io/github/doblon8/openpnp/capture/PropertyLimits.java

@@ -0,0 +1,4 @@
+package io.github.doblon8.openpnp.capture;
+
+public record PropertyLimits(int min, int max, int defaultValue) {
+}