protected Vec4 computeReferencePoint(DrawContext dc) {
if (dc.getViewportCenterPosition() != null)
return dc.getGlobe().computePointFromPosition(dc.getViewportCenterPosition());
java.awt.geom.Rectangle2D viewport = dc.getView().getViewport();
int x = (int) viewport.getWidth() / 2;
for (int y = (int) (0.5 * viewport.getHeight()); y >= 0; y--) {
Position pos = dc.getView().computePositionFromScreenPoint(x, y);
if (pos == null) continue;
return dc.getGlobe().computePointFromPosition(pos.getLatitude(), pos.getLongitude(), 0d);
}
return null;
}
// Rendering
public void draw(DrawContext dc) {
GL gl = dc.getGL();
boolean attribsPushed = false;
boolean modelviewPushed = false;
boolean projectionPushed = false;
try {
gl.glPushAttrib(
GL.GL_DEPTH_BUFFER_BIT
| GL.GL_COLOR_BUFFER_BIT
| GL.GL_ENABLE_BIT
| GL.GL_TEXTURE_BIT
| GL.GL_TRANSFORM_BIT
| GL.GL_VIEWPORT_BIT
| GL.GL_CURRENT_BIT);
attribsPushed = true;
gl.glDisable(GL.GL_TEXTURE_2D); // no textures
gl.glEnable(GL.GL_BLEND);
gl.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA);
gl.glDisable(GL.GL_DEPTH_TEST);
double width = this.size.width;
double height = this.size.height;
// Load a parallel projection with xy dimensions (viewportWidth, viewportHeight)
// into the GL projection matrix.
java.awt.Rectangle viewport = dc.getView().getViewport();
gl.glMatrixMode(javax.media.opengl.GL.GL_PROJECTION);
gl.glPushMatrix();
projectionPushed = true;
gl.glLoadIdentity();
double maxwh = width > height ? width : height;
gl.glOrtho(0d, viewport.width, 0d, viewport.height, -0.6 * maxwh, 0.6 * maxwh);
gl.glMatrixMode(GL.GL_MODELVIEW);
gl.glPushMatrix();
modelviewPushed = true;
gl.glLoadIdentity();
// Scale to a width x height space
// located at the proper position on screen
double scale = this.computeScale(viewport);
Vec4 locationSW = this.computeLocation(viewport, scale);
gl.glTranslated(locationSW.x(), locationSW.y(), locationSW.z());
gl.glScaled(scale, scale, 1);
// Compute scale size in real world
Position referencePosition = dc.getViewportCenterPosition();
if (referencePosition != null) {
Vec4 groundTarget = dc.getGlobe().computePointFromPosition(referencePosition);
Double distance = dc.getView().getEyePoint().distanceTo3(groundTarget);
this.pixelSize = dc.getView().computePixelSizeAtDistance(distance);
Double scaleSize = this.pixelSize * width * scale; // meter
String unitLabel = "m";
if (this.unit.equals(UNIT_METRIC)) {
if (scaleSize > 10000) {
scaleSize /= 1000;
unitLabel = "Km";
}
} else if (this.unit.equals(UNIT_IMPERIAL)) {
scaleSize *= 3.280839895; // feet
unitLabel = "ft";
if (scaleSize > 5280) {
scaleSize /= 5280;
unitLabel = "mile(s)";
}
}
// Rounded division size
int pot = (int) Math.floor(Math.log10(scaleSize));
if (!Double.isNaN(pot)) {
int digit = Integer.parseInt(String.format("%.0f", scaleSize).substring(0, 1));
double divSize = digit * Math.pow(10, pot);
if (digit >= 5) divSize = 5 * Math.pow(10, pot);
else if (digit >= 2) divSize = 2 * Math.pow(10, pot);
double divWidth = width * divSize / scaleSize;
// Draw scale
if (!dc.isPickingMode()) {
// Set color using current layer opacity
Color backColor = this.getBackgroundColor(this.color);
float[] colorRGB = backColor.getRGBColorComponents(null);
gl.glColor4d(
colorRGB[0],
colorRGB[1],
colorRGB[2],
(double) backColor.getAlpha() / 255d * this.getOpacity());
gl.glTranslated((width - divWidth) / 2, 0d, 0d);
this.drawScale(dc, divWidth, height);
colorRGB = this.color.getRGBColorComponents(null);
gl.glColor4d(colorRGB[0], colorRGB[1], colorRGB[2], this.getOpacity());
gl.glTranslated(-1d / scale, 1d / scale, 0d);
this.drawScale(dc, divWidth, height);
// Draw label
String label = String.format("%.0f ", divSize) + unitLabel;
gl.glLoadIdentity();
gl.glDisable(GL.GL_CULL_FACE);
drawLabel(
dc,
label,
locationSW.add3(
new Vec4(divWidth * scale / 2 + (width - divWidth) / 2, height * scale, 0)));
} else {
// Picking
this.pickSupport.clearPickList();
this.pickSupport.beginPicking(dc);
// Draw unique color across the map
Color color = dc.getUniquePickColor();
int colorCode = color.getRGB();
// Add our object(s) to the pickable list
this.pickSupport.addPickableObject(colorCode, this, referencePosition, false);
gl.glColor3ub((byte) color.getRed(), (byte) color.getGreen(), (byte) color.getBlue());
gl.glTranslated((width - divWidth) / 2, 0d, 0d);
this.drawRectangle(dc, divWidth, height);
// Done picking
this.pickSupport.endPicking(dc);
this.pickSupport.resolvePick(dc, dc.getPickPoint(), this);
}
}
}
} finally {
if (projectionPushed) {
gl.glMatrixMode(GL.GL_PROJECTION);
gl.glPopMatrix();
}
if (modelviewPushed) {
gl.glMatrixMode(GL.GL_MODELVIEW);
gl.glPopMatrix();
}
if (attribsPushed) gl.glPopAttrib();
}
}