Add a service interface for external routines

In particular, Font3D's triangulateGlyphs routine relies on the classes
GeometryInfo and NormalGenerator of package com.sun.j3d.utils.geometry,
which lives in the j3d-core-utils project, under a different license.
This means that historically, j3d-core and j3d-core-utils were mutually
dependent. We avoid the situation by using a service interface instead.

1 files changed, 40 insertions, 0 deletions

diff --git a/src/javax/media/j3d/GeometryService.java b/src/javax/media/j3d/GeometryService.java
new file mode 100644
index 0000000..346087c
--- /dev/null
+++ b/src/javax/media/j3d/GeometryService.java
@@ -0,0 +1,40 @@
+
+package javax.media.j3d;
+
+import java.util.ArrayList;
+
+import javax.vecmath.Point3f;
+
+/**
+ * A service interface for certain geometric operations that are not available
+ * in core Java 3D.
+ * <p>
+ * In particular, the {@code j3d-core-utils} project provides additional
+ * functionality under a different license, which is needed in some
+ * circumstances by core Java 3D. Thus, historically, these two projects have
+ * been co-dependent. This interface breaks the circular dependency by using
+ * Java's service discovery mechanism: if {@code j3d-core-utils} is present on
+ * the classpath, its {@code GeometryServiceImpl} will provide the functionality
+ * defined here. Or if not (i.e., no suitable {@code GeometryService}
+ * implementation can be discovered and instantiated}), then the Java3D core
+ * will fail as gracefully as possible.
+ * </p>
+ * 
+ * @see Font3D#triangulateGlyphs
+ */
+public interface GeometryService {
+
+	/**
+	 * Loops through each island, calling triangulator once per island. Combines
+	 * triangle data for all islands together in one object.
+	 * 
+	 * @param islandCounts TODO
+	 * @param outVerts TODO
+	 * @param contourCounts TODO
+	 * @param triangData TODO
+	 * @return total vertex count of the combined array
+	 */
+	int triangulateIslands(int[][] islandCounts, Point3f[][] outVerts,
+		int[] contourCounts, ArrayList<GeometryArray> triangData);
+
+}