import com.spire.presentation.*;
import com.spire.presentation.drawing.FillFormatType;
import com.spire.presentation.drawing.PictureFillType;
import com.spire.presentation.drawing.PresetShadow;
import java.awt.geom.Rectangle2D;
import java.awt.Color;

public class PptShadowDemo {

    public static void main(String[] args) throws Exception {
        // Create a new presentation instance
        Presentation presentation = new Presentation();

        // Access the first slide
        ISlide firstSlide = presentation.getSlides().get(0);

        // Draw a rectangle shape
        Rectangle2D bounds = new Rectangle2D.Float(120, 80, 180, 150);
        IAutoShape rectangleShape = firstSlide.getShapes().appendShape(ShapeType.RECTANGLE, bounds);

        // Load and stretch an image into the shape
        rectangleShape.getFill().setFillType(FillFormatType.PICTURE);
        rectangleShape.getFill().getPictureFill().getPicture().setUrl("C:\\Users\\Administrator\\Desktop\\cow.png");
        rectangleShape.getFill().getPictureFill().setFillType(PictureFillType.STRETCH);
        rectangleShape.getLine().setFillType(FillFormatType.NONE);

        // Configure a preset shadow effect
        PresetShadow shadow = new PresetShadow();
        shadow.setPreset(PresetShadowValue.BACK_RIGHT_PERSPECTIVE);
        shadow.getColorFormat().setColor(Color.lightGray);

        // Attach the shadow to the shape
        rectangleShape.getEffectDag().setPresetShadowEffect(shadow);

        // Write the output file
        presentation.saveToFile("ShapeShadow.pptx", FileFormat.PPTX_2013);
    }
}

Shadow effects—including inner, outer, and soft-edge variants—enhance the depth and visual appeal of shapes. The libray must be available in the project claspsath. With Maven, reference it as follows:

<repositories>
    <repository>
        <id>com.e-iceblue</id>
        <url>http://repo.e-iceblue.cn/repository/maven-public/</url>
    </repository>
</repositories>

<dependencies>
    <dependency>
        <groupId>e-iceblue</groupId>
        <artifactId>spire.presentation.free</artifactId>
        <version>2.6.1</version>
    </dependency>
</dependencies>

After execution, the generated PowerPoint file displays the image-filled rectangle with a perspective shadow cast behind it.