Merge pull request #103 from javagl/builder-extensions

Extensions and bugfixes for the model builder package

jgltf-model-builder/src/main/java/de/javagl/jgltf/model/creation/AccessorModels.java

@@ -31,12 +31,15 @@
 import java.nio.IntBuffer;
 import java.nio.ShortBuffer;
 
+import de.javagl.jgltf.model.AccessorData;
 import de.javagl.jgltf.model.AccessorDatas;
 import de.javagl.jgltf.model.AccessorModel;
 import de.javagl.jgltf.model.Accessors;
 import de.javagl.jgltf.model.BufferViewModel;
 import de.javagl.jgltf.model.ElementType;
 import de.javagl.jgltf.model.GltfConstants;
+import de.javagl.jgltf.model.GltfModel;
+import de.javagl.jgltf.model.MeshPrimitiveModel;
 import de.javagl.jgltf.model.impl.DefaultAccessorModel;
 import de.javagl.jgltf.model.io.Buffers;
 
@@ -47,10 +50,56 @@
  * {@link AccessorModel#getAccessorData() accessor data} that
  * simply represents the data that was given at construction time.
  * The instances do <b>not</b> have an associated {@link BufferViewModel}
- * instance. 
+ * instance.<br>
+ * <br>
+ * The instances of accessor models that are created by this class
+ * are supposed to be used during the construction of a glTF model,
+ * using the {@link GltfModelBuilder}: They hold the data of the
+ * model elements (for example, attributes in a {@link MeshPrimitiveModel}).<br>
+ * <br>
+ * The {@link GltfModelBuilder} will use the accessor data internally,
+ * in order to build the associated buffers and buffer views.<br>
+ * <br>
+ * This class offers some convenience methods for commonly used accessor
+ * model types - for example, 3D floating point vectors (positions and
+ * normals), or unsigned int scalar values (for indices).<br>
+ * <br>
+ * Arbitrary (more specific) accessor model types can be constructed with
+ * the {@link #create(int, String, boolean, ByteBuffer)} method, which
+ * receives all information that is required for the accessor model.
+ * This method expects the data to be given as a byte buffer. When the
+ * input data is a <code>FloatBuffer</code>, then the byte buffer can be
+ * created with the utility methods in the {@link Buffers} class - for
+ * example, {@link Buffers#createByteBufferFrom(FloatBuffer)}.
  */
 public class AccessorModels 
 {
+    /**
+     * Creates a copy of the given accessor model, only based on its
+     * {@link AccessorData}.<br>
+     * <br>
+     * This will return a model that has the same data type and data
+     * as the given model, but without an associated buffer view.<br>
+     * <br>
+     * This may be used to create a copy of an accessor model from
+     * one {@link GltfModel}, and pass it to a {@link GltfModelBuilder}
+     * for the construction of a new {@link GltfModel}.
+     *
+     * @param input The input
+     * @return The copy
+     */
+    public static DefaultAccessorModel copy(AccessorModel input)
+    {
+        AccessorData inputAccessorData = input.getAccessorData();
+        ByteBuffer byteBuffer = inputAccessorData.createByteBuffer();
+        DefaultAccessorModel copy = AccessorModels.create(
+            input.getComponentType(),
+            input.getElementType().toString(),
+            input.isNormalized(),
+            byteBuffer);
+        return copy;
+    }
+
     /**
      * Creates a new {@link AccessorModel} with the component type
      * <code>GL_UNSIGNED_INT</code> and the type <code>"SCALAR"</code>.
@@ -330,7 +379,7 @@ public static DefaultAccessorModel create(
             throw new IllegalArgumentException(
                 "Invalid data for type " + type + " accessor with "
                 + Accessors.getDataTypeForAccessorComponentType(componentType)
-                + "components: The data length is " + byteBuffer.capacity() 
+                + " components: The data length is " + byteBuffer.capacity()
                 + " which is not divisble by " + numBytesPerElement);
         }
         int count = byteBuffer.capacity() / numBytesPerElement;

jgltf-model-builder/src/main/java/de/javagl/jgltf/model/creation/BufferBuilderStrategy.java

@@ -91,7 +91,6 @@ void processSkinModels(
 
     /**
      * Process all {@link AccessorModel} instances from the given collection
-     * by the given {@link SkinModel} instances
      * 
      * @param accessorModels The {@link AccessorModel} instances
      */

jgltf-model-builder/src/main/java/de/javagl/jgltf/model/creation/BufferStructure.java

@@ -428,8 +428,8 @@ public boolean isPaddingByteIndex(BufferModel bufferModel, int index)
      * contained in the given collection
      * 
      * @param prefix The prefix for the ID
-     * @param existingIds The existing URI strings
-     * @return The new URI string
+     * @param existingIds The existing ID strings
+     * @return The new ID string
      */
     private String createId(String prefix,
         Collection<? extends String> existingIds)

jgltf-model-builder/src/main/java/de/javagl/jgltf/model/creation/BufferStructureBuilder.java

@@ -44,6 +44,7 @@
 import de.javagl.jgltf.model.BufferViewModel;
 import de.javagl.jgltf.model.ElementType;
 import de.javagl.jgltf.model.GltfConstants;
+import de.javagl.jgltf.model.GltfException;
 import de.javagl.jgltf.model.impl.DefaultAccessorModel;
 import de.javagl.jgltf.model.impl.DefaultBufferModel;
 import de.javagl.jgltf.model.impl.DefaultBufferViewModel;
@@ -147,6 +148,30 @@ public int getNumBufferModels()
     {
         return bufferStructure.getBufferModels().size();
     }
+
+    /**
+     * Returns the number of {@link AccessorModel} instances that have been 
+     * added, but for which no {@link BufferViewModel} has been created
+     * yet.
+     * 
+     * @return The number of pending {@link AccessorModel} instances
+     */
+    public int getNumCurrentAccessorModels() 
+    {
+        return currentAccessorModels.size();
+    }
+
+    /**
+     * Returns the number of {@link BufferViewModel} instances that have been 
+     * added, but for which no {@link BufferModel} has been created
+     * yet.
+     * 
+     * @return The number of pending {@link BufferViewModel} instances
+     */
+    public int getNumCurrentBufferViewModels() 
+    {
+        return currentBufferViewModels.size();
+    }
 
     /**
      * Create an {@link AccessorModel} in the {@link BufferStructure} that 
@@ -281,10 +306,18 @@ public AccessorModel createAccessorModel(String idPrefix,
      * 
      * @param idPrefix The ID prefix of the {@link AccessorModel}
      * @param accessorModel The {@link AccessorModel}
+     * @throws GltfException If the given accessor model already has an
+     * associated buffer view
      */
     public void addAccessorModel(
         String idPrefix, DefaultAccessorModel accessorModel)
     {
+        BufferViewModel bufferViewModel = accessorModel.getBufferViewModel();
+        if (bufferViewModel != null)
+        {
+            throw new GltfException(
+                "The accessor already contains a buffer view");
+        }
         bufferStructure.addAccessorModel(accessorModel, idPrefix);
         currentAccessorModels.add(accessorModel);
     }

jgltf-model-builder/src/main/java/de/javagl/jgltf/model/creation/BufferStructureGltfV1.java

@@ -43,7 +43,10 @@
 
 /**
  * Utility methods for creating the glTF 1.0 elements that correspond to
- * a {@link BufferStructure}
+ * a {@link BufferStructure}.<br>
+ * <br>
+ * This class is only intended for internal use, and may be removed in
+ * the future.
  */
 public class BufferStructureGltfV1
 {

jgltf-model-builder/src/main/java/de/javagl/jgltf/model/creation/BufferStructureGltfV2.java

@@ -42,7 +42,10 @@
 
 /**
  * Utility methods for creating the glTF 2.0 elements that correspond to
- * a {@link BufferStructure}
+ * a {@link BufferStructure}.<br>
+ * <br>
+ * This class is only intended for internal use, and may be removed in
+ * the future.
  */
 public class BufferStructureGltfV2
 {

jgltf-model-builder/src/main/java/de/javagl/jgltf/model/creation/BufferStructures.java

@@ -38,7 +38,8 @@
 import de.javagl.jgltf.model.io.GltfReference;
 
 /**
- * Utility methods related to {@link BufferStructure} instances.
+ * Utility methods related to {@link BufferStructure} instances.<br>
+ * <br>
  * Only intended for internal use.
  */
 public class BufferStructures