fix: retrieval of ArrayDouble output options (fixes #183) (#184)

* fix: retrieval of ArrayDouble output options (fixes #183)

* More array offset fixes for ArrayImage and ArrayInt

* fix: Bump JVM version to 25 for CI

Author: jbaiter

.github/workflows/checks.yml

@@ -17,8 +17,8 @@ jobs:
       - name: Setup Java
         uses: actions/setup-java@v4
         with:
-          distribution: "temurin"
-          java-version: 23
+          distribution: "corretto"
+          java-version: 25 # run a newer version on macOS to work around libzip linking issues
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v3

core/src/main/java/app/photofox/vipsffm/VipsInvoker.java

@@ -175,7 +175,7 @@ private static void readGValueAndSetOptionValue(
                 var numberOfElements = numberOfValuesPointer.get(C_INT, 0);
                 var list = new ArrayList<Integer>();
                 for (int i = 0; i < numberOfElements; i++) {
-                    var value = valuesPointer.get(C_INT, i);
+                    var value = valuesPointer.get(C_INT, i * C_INT.byteSize());
                     list.add(value);
                 }
                 o.setValue(list);
@@ -188,7 +188,7 @@ private static void readGValueAndSetOptionValue(
                 var numberOfElements = numberOfValuesPointer.get(C_INT, 0);
                 var list = new ArrayList<Double>();
                 for (int i = 0; i < numberOfElements; i++) {
-                    var value = valuesPointer.get(C_DOUBLE, i);
+                    var value = valuesPointer.get(C_DOUBLE, i * C_DOUBLE.byteSize());
                     list.add(value);
                 }
                 o.setValue(list);
@@ -201,7 +201,7 @@ private static void readGValueAndSetOptionValue(
                 var numberOfElements = numberOfValuesPointer.get(C_INT, 0);
                 var list = new ArrayList<VImage>();
                 for (int i = 0; i < numberOfElements; i++) {
-                    var pointer = valuesPointer.get(C_POINTER, i);
+                    var pointer = valuesPointer.get(C_POINTER, i * C_POINTER.byteSize());
                     pointer = refGObjectToArenaScope(arena, pointer);
                     var value = new VImage(arena, pointer);
                     list.add(value);

sample/src/main/kotlin/vipsffm/SampleRunner.kt

@@ -20,6 +20,7 @@ import vipsffm.sample.VImageGetPagesSample
 import vipsffm.sample.VImageGetSetSample
 import vipsffm.sample.VImageJoinSample
 import vipsffm.sample.VImageFromMemoryToMemorySample
+import vipsffm.sample.VImageGetPointSample
 import vipsffm.sample.VImageStaticThumbnailSample
 import vipsffm.sample.VOptionHyphenSample
 import vipsffm.sample.VSourceTargetSample
@@ -53,6 +54,7 @@ object SampleRunner {
             VImageStreamSample,
             VImageStaticThumbnailSample,
             VImageGetPagesSample,
+            VImageGetPointSample,
             HelperGetSetMetadataSample,
             VImageGetSetSample,
             VImageFindTrimSample,

sample/src/main/kotlin/vipsffm/sample/VImageGetPointSample.kt

@@ -0,0 +1,43 @@
+package vipsffm.sample
+
+import app.photofox.vipsffm.VBlob
+import app.photofox.vipsffm.VImage
+import org.slf4j.LoggerFactory
+import vipsffm.RunnableSample
+import java.lang.foreign.Arena
+import java.nio.file.Path
+
+/**
+ * Sample to get the color values at a specific point in an image
+ */
+object VImageGetPointSample: RunnableSample {
+
+    val logger = LoggerFactory.getLogger(VImageGetPointSample::class.java)
+
+    override fun run(arena: Arena, workingDirectory: Path): Result<Unit> {
+        val sourceImage = VImage
+            .newFromFile(
+                arena,
+                "sample/src/main/resources/sample_images/rabbit.jpg"
+            )
+
+        val point = sourceImage.getpoint(100, 100)
+        if (point.size != 3) {
+            return Result.failure(
+                RuntimeException("unexpected number of channels at 100,100: ${point.size}")
+            )
+        }
+        val red = point.get(0).toInt()
+        val green = point.get(1).toInt()
+        val blue = point.get(2).toInt()
+        if (red != 154 ||
+            green != 165 ||
+            blue != 135) {
+            return Result.failure(
+                RuntimeException("unexpected pixel value at 100,100: R=${red} G=${green} B=${blue}")
+            )
+        }
+
+        return Result.success(Unit)
+    }
+}