src/main/java/eu/svjatoslav/sixth/e3d/gui/RenderingContext.java

   1 /*
   2  * Sixth 3D engine. Author: Svjatoslav Agejenko.
   3  * This project is released under Creative Commons Zero (CC0) license.
   4  */
   5 package eu.svjatoslav.sixth.e3d.gui;
   6
   7 import eu.svjatoslav.sixth.e3d.geometry.Point2D;
   8 import eu.svjatoslav.sixth.e3d.gui.humaninput.MouseEvent;
   9 import eu.svjatoslav.sixth.e3d.gui.humaninput.MouseInteractionController;
  10
  11 import java.awt.*;
  12 import java.awt.image.BufferedImage;
  13 import java.awt.image.DataBufferByte;
  14 import java.awt.image.WritableRaster;
  15
  16 public class RenderingContext {
  17
  18     public static final int bufferedImageType = BufferedImage.TYPE_4BYTE_ABGR;
  19     public final Graphics2D graphics;
  20     public final byte[] pixels;
  21     public final int width;
  22     public final int height;
  23     /**
  24      * Center of the screen in screen space (pixels).
  25      * This is the point where (0,0) coordinate of the world space is rendered.
  26      */
  27     public final Point2D centerCoordinate;
  28
  29     /**
  30      * Zoom factor. The bigger the value, the more zoomed in the view is.
  31      */
  32     public final double zoom;
  33     final BufferedImage bufferedImage;
  34     /**
  35      * Number of frame that is currently being rendered.
  36      * Every frame has its own number.
  37      */
  38     public int frameNumber = 0;
  39
  40     /**
  41      * UI component that mouse is currently hovering over.
  42      */
  43     private MouseInteractionController objectPreviouslyUnderMouseCursor;
  44     /**
  45      * Mouse click event that needs to be processed.
  46      * This event is processed only once per frame.
  47      * If there are multiple objects under mouse cursor, the top-most object will receive the event.
  48      * If there are no objects under mouse cursor, the event will be ignored.
  49      * If there is no event, this field will be null.
  50      * This field is set to null after the event is processed.
  51      */
  52     private MouseEvent mouseEvent;
  53     /**
  54      * UI component that mouse is currently hovering over.
  55      */
  56     private MouseInteractionController currentObjectUnderMouseCursor;
  57
  58     public RenderingContext(final int width, final int height) {
  59         this.width = width;
  60         this.height = height;
  61         this.centerCoordinate = new Point2D(width / 2d, height / 2d);
  62         this.zoom = width / 3d;
  63
  64         bufferedImage = new BufferedImage(width, height, bufferedImageType);
  65
  66         final WritableRaster raster = bufferedImage.getRaster();
  67         final DataBufferByte dbi = (DataBufferByte) raster.getDataBuffer();
  68         pixels = dbi.getData();
  69
  70         graphics = (Graphics2D) bufferedImage.getGraphics();
  71         graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
  72         graphics.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
  73     }
  74
  75     public void prepareForNewFrameRendering() {
  76         mouseEvent = null;
  77         currentObjectUnderMouseCursor = null;
  78     }
  79
  80     public MouseEvent getMouseEvent() {
  81         return mouseEvent;
  82     }
  83
  84     public void setMouseEvent(MouseEvent mouseEvent) {
  85         this.mouseEvent = mouseEvent;
  86     }
  87
  88     /**
  89      * Called when given object was detected under mouse cursor, while processing {@link #mouseEvent}.
  90      * Because objects are rendered back to front. The last method caller will set the top-most object, if
  91      * there are multiple objects under mouse cursor.
  92      */
  93     public void setCurrentObjectUnderMouseCursor(MouseInteractionController currentObjectUnderMouseCursor) {
  94         this.currentObjectUnderMouseCursor = currentObjectUnderMouseCursor;
  95     }
  96
  97     /**
  98      * @return <code>true</code> if view update is needed as a consequence of this mouse event.
  99      */
 100     public boolean handlePossibleComponentMouseEvent() {
 101         if (mouseEvent == null) return false;
 102
 103         boolean viewRepaintNeeded = false;
 104
 105         if (objectPreviouslyUnderMouseCursor != currentObjectUnderMouseCursor) {
 106             // Mouse cursor has just entered or left component.
 107             viewRepaintNeeded = objectPreviouslyUnderMouseCursor != null && objectPreviouslyUnderMouseCursor.mouseExited();
 108             viewRepaintNeeded |= currentObjectUnderMouseCursor != null && currentObjectUnderMouseCursor.mouseEntered();
 109             objectPreviouslyUnderMouseCursor = currentObjectUnderMouseCursor;
 110         }
 111
 112         if (mouseEvent.button != 0 && currentObjectUnderMouseCursor != null) {
 113             // Mouse button was clicked on some component.
 114             viewRepaintNeeded |= currentObjectUnderMouseCursor.mouseClicked(mouseEvent.button);
 115         }
 116
 117         return viewRepaintNeeded;
 118     }
 119
 120 }