I am developing a small chart app to monitor the blood sugar with the MPAndroidChart library.
Is there a way to draw the text inside the circle without offset?
As suggested in another post, i put in a slight y-offset (different y-data for circle and text) and achieved a result which is ok.
But if there are only two values the text and circle do not align.
I am not that familiar with modifying the yAxis Renderer, do you know how to find the formula behind the offset for the labels? (would be great to just recalculate it..)
Similar problem: How to place the text values inside in MPAndroidChart circle?
With manual offset between text and circle y-data
Due to zooming in on y-axis (less data points and range on y-axis) the manuel offset is not working well here..
Otherwise awesome library PhilJay !!
EDIT: I have found a easy and sufficient solution:
Override the drawValues method from LineChartRenderer**
In LineChartRenderer.java -> drawValues the text is vertically shifted by this line:
drawValue(c, formatter.getPointLabel(entry), x, y - valOffset, dataSet.getValueTextColor(j / 2));
So to get rid of the "- valOffset":
1.Override the drawValues method
Create a new java file "CenteredTextLineChartRenderer.java" and override method drawValues from LineChartRenderer
2.Modify the y-valOffset to y+textHeight*0.35f
Add float textHeight = dataSet.getValueTextSize();
public class CenteredTextLineChartRenderer extends LineChartRenderer {
public CenteredTextLineChartRenderer(LineDataProvider chart, ChartAnimator animator, ViewPortHandler viewPortHandler) {
super(chart, animator, viewPortHandler);
}
//Modified drawValues Method
// Center label on coordinate instead of applying a valOffset
#Override
public void drawValues(Canvas c) {
if (isDrawingValuesAllowed(mChart)) {
List<ILineDataSet> dataSets = mChart.getLineData().getDataSets();
for (int i = 0; i < dataSets.size(); i++) {
ILineDataSet dataSet = dataSets.get(i);
float textHeight = dataSet.getValueTextSize();
if (!shouldDrawValues(dataSet) || dataSet.getEntryCount() < 1)
continue;
// apply the text-styling defined by the DataSet
applyValueTextStyle(dataSet);
Transformer trans = mChart.getTransformer(dataSet.getAxisDependency());
// make sure the values do not interfear with the circles
int valOffset = (int) (dataSet.getCircleRadius() * 1.75f);
if (!dataSet.isDrawCirclesEnabled())
valOffset = valOffset / 2;
mXBounds.set(mChart, dataSet);
float[] positions = trans.generateTransformedValuesLine(dataSet, mAnimator.getPhaseX(), mAnimator
.getPhaseY(), mXBounds.min, mXBounds.max);
ValueFormatter formatter = dataSet.getValueFormatter();
MPPointF iconsOffset = MPPointF.getInstance(dataSet.getIconsOffset());
iconsOffset.x = Utils.convertDpToPixel(iconsOffset.x);
iconsOffset.y = Utils.convertDpToPixel(iconsOffset.y);
for (int j = 0; j < positions.length; j += 2) {
float x = positions[j];
float y = positions[j + 1];
if (!mViewPortHandler.isInBoundsRight(x))
break;
if (!mViewPortHandler.isInBoundsLeft(x) || !mViewPortHandler.isInBoundsY(y))
continue;
Entry entry = dataSet.getEntryForIndex(j / 2 + mXBounds.min);
if (dataSet.isDrawValuesEnabled()) {
//drawValue(c, formatter.getPointLabel(entry), x, y - valOffset, dataSet.getValueTextColor(j / 2));
drawValue(c, formatter.getPointLabel(entry), x, y+textHeight*0.35f, dataSet.getValueTextColor(j / 2));
}
if (entry.getIcon() != null && dataSet.isDrawIconsEnabled()) {
Drawable icon = entry.getIcon();
Utils.drawImage(
c,
icon,
(int)(x + iconsOffset.x),
(int)(y + iconsOffset.y),
icon.getIntrinsicWidth(),
icon.getIntrinsicHeight());
}
}
MPPointF.recycleInstance(iconsOffset);
}
}
}
}
3.Set your own LineChart renderer to your modified drawValues class
LineChart mChart = (LineChart) mainActivity.findViewById(R.id.LineChart);
mChart.setRenderer(new CenteredTextLineChartRenderer(mChart,mChart.getAnimator(),mChart.getViewPortHandler()));
Run your code and manually adapt the 0.35f offset in your CenteredTextLineChartRenderer class
Now your text is always vertically centered!
IMPORTANT: With deleting the valOffset your label is not vertically centered as the text anchor is not in the center of your text label. So you have to insert a manual offset "textHeight*0.35f" (just try it out).
I have code written using PDFBox API that highlights the words in a PDF but when I convert highlighted PDF pages to images, then whatever I have highlighted gets disappeared from the image.
Below screenshot is with highlighted text, for highlighting I have used PDFBox's PDAnnotationTextMarkup class:
Highlighted PDF Page
Below is the image after converting the pdf page to image:
Highlighted PDF Page Image after converting
Below is the code I have used for converting PDF to Image:
PDDocument document = PDDocument.load(new File(pdfFilename));
PDFRenderer pdfRenderer = new PDFRenderer(document);
int pageCounter = 0;
for (PDPage page : document.getPages())
{
BufferedImage bim = pdfRenderer.renderImageWithDPI(pageCounter, 300, ImageType.RGB);
ImageIOUtil.writeImage(bim, pdfFilename + "-" + (pageCounter++) + ".png", 300);
}
document.close();
Please suggest what is wrong here, why PDFRenderer not able to take PDF page image along with the highlighted red box.
Below is the code I used to highlight the text in PDF:
private void highlightText(String pdfFilePath, String highlightedPdfFilePath) {
try {
// Loading an existing document
File file = new File(highlightedPdfFilePath);
if (!file.exists()) {
file = new File(pdfFilePath);
}
PDDocument document = PDDocument.load(file);
// extended PDFTextStripper class
PDFTextStripper stripper = new PDFTextHighlighter();
// Get number of pages
int number_of_pages = document.getDocumentCatalog().getPages().getCount();
// The method writeText will invoke an override version of
// writeString
Writer dummy = new OutputStreamWriter(new ByteArrayOutputStream());
stripper.writeText(document, dummy);
// Print collected information
System.out.println("tokenStream:::"+tokenStream);
System.out.println("tokenStream size::"+tokenStream.size());
System.out.println("coordinates size::"+coordinates.size());
double page_height;
double page_width;
double width, height, minx, maxx, miny, maxy;
int rotation;
// scan each page and highlitht all the words inside them
for (int page_index = 0; page_index < number_of_pages; page_index++) {
// get current page
PDPage page = document.getPage(page_index);
// Get annotations for the selected page
List<PDAnnotation> annotations = page.getAnnotations();
// Define a color to use for highlighting text
PDColor red = new PDColor(new float[] { 1, 0, 0 }, PDDeviceRGB.INSTANCE);
// Page height and width
page_height = page.getMediaBox().getHeight();
page_width = page.getMediaBox().getWidth();
// Scan collected coordinates
for (int i = 0; i < coordinates.size(); i++) {
if (!differencePgaeNumber.contains(page_index)) {
differencePgaeNumber.add(page_index);
}
// if the current coordinates are not related to the current
// page, ignore them
if ((int) coordinates.get(i)[4] != (page_index + 1))
continue;
else {
// get rotation of the page...portrait..landscape..
rotation = (int) coordinates.get(i)[7];
// page rotated of 90degrees
if (rotation == 90) {
height = coordinates.get(i)[5];
width = coordinates.get(i)[6];
width = (page_height * width) / page_width;
// define coordinates of a rectangle
maxx = coordinates.get(i)[1];
minx = coordinates.get(i)[1] - height;
miny = coordinates.get(i)[0];
maxy = coordinates.get(i)[0] + width;
} else // i should add here the cases -90/-180 degrees
{
height = coordinates.get(i)[5];
minx = coordinates.get(i)[0];
maxx = coordinates.get(i)[2];
miny = page_height - coordinates.get(i)[1];
maxy = page_height - coordinates.get(i)[3] + height;
}
// Add an annotation for each scanned word
PDAnnotationTextMarkup txtMark = new PDAnnotationTextMarkup(
PDAnnotationTextMarkup.SUB_TYPE_HIGHLIGHT);
txtMark.setColor(red);
txtMark.setConstantOpacity((float) 0.3); // 30%
// transparent
PDRectangle position = new PDRectangle();
position.setLowerLeftX((float) minx);
position.setLowerLeftY((float) miny);
position.setUpperRightX((float) maxx);
position.setUpperRightY((float) ((float) maxy + height));
txtMark.setRectangle(position);
float[] quads = new float[8];
quads[0] = position.getLowerLeftX(); // x1
quads[1] = position.getUpperRightY() - 2; // y1
quads[2] = position.getUpperRightX(); // x2
quads[3] = quads[1]; // y2
quads[4] = quads[0]; // x3
quads[5] = position.getLowerLeftY() - 2; // y3
quads[6] = quads[2]; // x4
quads[7] = quads[5]; // y5
txtMark.setQuadPoints(quads);
txtMark.setContents(tokenStream.get(i).toString());
annotations.add(txtMark);
}
}
}
// Saving the document in a new file
File highlighted_doc = new File(highlightedPdfFilePath);
document.save(highlighted_doc);
document.close();
} catch (IOException e) {
System.out.println(e);
}
}
You need to construct the visual appearance of the annotation with this call:
txtMark.constructAppearances(document);
I have created a watermark text that is vertically centered.
This is the line I used
PdfPatternPainter.showTextAlignedKerned(Element.ALIGN_MIDDLE,
string, x, y, -90);
What i want to do now is to make the watermark diagonal. changing the angle value will make it diagonal, but then its x,y position is not centered anymore.
this is my current method
public static void createWaterMarkPDF(ArrayList<String> watermark, PdfReader reader, PdfStamper stamper) throws Exception {
Rectangle pageSize = reader.getPageSize(1);
final float WATERMARK_PAGE_ANGLE = 270;
BaseFont font = BaseFont.createFont(BaseFont.HELVETICA, BaseFont.WINANSI, BaseFont.NOT_EMBEDDED);
PdfPatternPainter painter = stamper.getOverContent(1).createPattern(pageSize.getWidth(), pageSize.getHeight());
painter.setColorStroke(new BaseColor(192, 192, 192));
int FONT_SIZE = 80;
painter.beginText();
painter.setTextRenderingMode(PdfPatternPainter.TEXT_RENDER_MODE_FILL);
painter.setFontAndSize(font, FONT_SIZE);
for (int i=0; i<watermark.size(); i++) {
String string = watermark.get(i);
// Values are opposite since we are doing a vertical alignment angle
float width = font.getAscentPoint(string, FONT_SIZE) + font.getDescentPoint(string, FONT_SIZE);
float height = painter.getEffectiveStringWidth(string, true);
float x = (pageSize.getWidth() - width) / 2;
if (i == 0)
x += (width * 3);
else if (i == 2)
x -= (width * 3);
painter.showTextAlignedKerned(Element.ALIGN_MIDDLE,
string, x,
Util.transformY(pageSize, (pageSize.getHeight() - height) / 2),
WATERMARK_PAGE_ANGLE);
}
painter.endText();
// Transparency of watermark
PdfGState state = new PdfGState();
state.setFillOpacity(0.1f);
for (int i=reader.getNumberOfPages(); i>0; i--) {
Rectangle thisPageSize = reader.getPageSize(i);
PdfContentByte overContent = stamper.getOverContent(i);
overContent.setColorFill(new PatternColor(painter));
overContent.setGState(state);
overContent.rectangle(thisPageSize.getLeft(), thisPageSize.getBottom(), thisPageSize.getWidth(), thisPageSize.getHeight());
overContent.fill();
}
}
it draws vertical lines and centered. watermark is an ArrayList. you can add 3 strings.
if i change the angle to , say 300 (or -60) to make it diagonal, the positioning is whacked. do i need to use an AffineTransform here? although i already tried, didnt work for me unless i lacked something here?
I have a pdf file where-in I am adding a stamp to all it's pages.
But, the problem is, the stamp is added to the upper-left corner of each page. If, the page has text in that part, the stamp appears on the text.
My question is, is there any method by which I can read each page and if there is no text in that part add the stamp else search for nearest available free space, just like what a density scanner does?
I am using IText and Java 1.7.
The free space fider class and the distance calculation function are the same that is there in the accepted answer.
Following is the edited code I am using:
// The resulting PDF file
String RESULT = "K:\\DCIN_TER\\DCIN_EPU2\\CIRCUIT FROM BRANCH\\RAINBOW ORDERS\\" + jtfSONo.getText().trim() + "\\PADR Release\\Final PADR Release 1.pdf";
// Create a reader
PdfReader reader = new PdfReader("K:\\DCIN_TER\\DCIN_EPU2\\CIRCUIT FROM BRANCH\\RAINBOW ORDERS\\" + jtfSONo.getText().trim() + "\\PADR Release\\Final PADR Release.pdf");
// Create a stamper
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(RESULT));
// Loop over the pages and add a footer to each page
int n = reader.getNumberOfPages();
for(int i = 1; i <= n; i++)
{
Collection<Rectangle2D> rectangles = find(reader, 300, 100, n, stamper); // minimum width & height of a rectangle
Iterator itr = rectangles.iterator();
while(itr.hasNext())
{
System.out.println(itr.next());
}
if(!(rectangles.isEmpty()) && (rectangles.size() != 0))
{
Rectangle2D best = null;
double bestDist = Double.MAX_VALUE;
Point2D.Double point = new Point2D.Double(200, 400);
float x = 0, y = 0;
for(Rectangle2D rectangle: rectangles)
{
double distance = distance(rectangle, point);
if(distance < bestDist)
{
best = rectangle;
bestDist = distance;
x = (float) best.getX();
y = (float) best.getY();
int left = (int) best.getMinX();
int right = (int) best.getMaxX();
int top = (int) best.getMaxY();
int bottom = (int) best.getMinY();
System.out.println("x : " + x);
System.out.println("y : " + y);
System.out.println("left : " + left);
System.out.println("right : " + right);
System.out.println("top : " + top);
System.out.println("bottom : " + bottom);
}
}
getFooterTable(i, n).writeSelectedRows(0, -1, x, y, stamper.getOverContent(i)); // 0, -1 indicates 1st row, 1st column upto last row and last column
}
else
getFooterTable(i, n).writeSelectedRows(0, -1, 94, 140, stamper.getOverContent(i)); // bottom left corner
}
// Close the stamper
stamper.close();
// Close the reader
reader.close();
public Collection<Rectangle2D> find(PdfReader reader, float minWidth, float minHeight, int page, PdfStamper stamper) throws IOException
{
Rectangle cropBox = reader.getCropBox(page);
Rectangle2D crop = new Rectangle2D.Float(cropBox.getLeft(), cropBox.getBottom(), cropBox.getWidth(), cropBox.getHeight());
FreeSpaceFinder finder = new FreeSpaceFinder(crop, minWidth, minHeight);
PdfReaderContentParser parser = new PdfReaderContentParser(reader);
parser.processContent(page, finder);
System.out.println("finder.freeSpaces : " + finder.freeSpaces);
return finder.freeSpaces;
}
// Create a table with page X of Y, #param x the page number, #param y the total number of pages, #return a table that can be used as footer
public static PdfPTable getFooterTable(int x, int y)
{
java.util.Date date = new java.util.Date();
SimpleDateFormat sdf = new SimpleDateFormat("dd MMM yyyy");
String month = sdf.format(date);
System.out.println("Month : " + month);
PdfPTable table = new PdfPTable(1);
table.setTotalWidth(120);
table.setLockedWidth(true);
table.getDefaultCell().setFixedHeight(20);
table.getDefaultCell().setBorder(Rectangle.TOP);
table.getDefaultCell().setBorder(Rectangle.LEFT);
table.getDefaultCell().setBorder(Rectangle.RIGHT);
table.getDefaultCell().setBorderColorTop(BaseColor.BLUE);
table.getDefaultCell().setBorderColorLeft(BaseColor.BLUE);
table.getDefaultCell().setBorderColorRight(BaseColor.BLUE);
table.getDefaultCell().setBorderWidthTop(1f);
table.getDefaultCell().setBorderWidthLeft(1f);
table.getDefaultCell().setBorderWidthRight(1f);
table.getDefaultCell().setHorizontalAlignment(Element.ALIGN_CENTER);
Font font1 = new Font(FontFamily.HELVETICA, 10, Font.BOLD, BaseColor.BLUE);
table.addCell(new Phrase("CONTROLLED COPY", font1));
table.getDefaultCell().setFixedHeight(20);
table.getDefaultCell().setBorder(Rectangle.LEFT);
table.getDefaultCell().setBorder(Rectangle.RIGHT);
table.getDefaultCell().setBorderColorLeft(BaseColor.BLUE);
table.getDefaultCell().setBorderColorRight(BaseColor.BLUE);
table.getDefaultCell().setBorderWidthLeft(1f);
table.getDefaultCell().setBorderWidthRight(1f);
table.getDefaultCell().setHorizontalAlignment(Element.ALIGN_CENTER);
Font font = new Font(FontFamily.HELVETICA, 10, Font.BOLD, BaseColor.RED);
table.addCell(new Phrase(month, font));
table.getDefaultCell().setFixedHeight(20);
table.getDefaultCell().setBorder(Rectangle.LEFT);
table.getDefaultCell().setBorder(Rectangle.RIGHT);
table.getDefaultCell().setBorder(Rectangle.BOTTOM);
table.getDefaultCell().setBorderColorLeft(BaseColor.BLUE);
table.getDefaultCell().setBorderColorRight(BaseColor.BLUE);
table.getDefaultCell().setBorderColorBottom(BaseColor.BLUE);
table.getDefaultCell().setBorderWidthLeft(1f);
table.getDefaultCell().setBorderWidthRight(1f);
table.getDefaultCell().setBorderWidthBottom(1f);
table.getDefaultCell().setHorizontalAlignment(Element.ALIGN_CENTER);
table.addCell(new Phrase("BLR DESIGN DEPT.", font1));
return table;
}
is there any method by which I can read each page and if there is no text in that part add the stamp else search for nearest available free space, just like what a density scanner does?
iText does not offer that functionality out of the box. Depending of what kind of content you want to evade, though, you might consider either rendering the page to an image and looking for white spots in the image or doing text extraction with a strategy that tries to find locations without text.
The first alternative, analyzing a rendered version of the page, would be the focus of a separate question as an image processing library would have to be chosen first.
There are a number of situations, though, in which that first alternative is not the best way to go. E.g. if you only want to evade text but not necessarily graphics (like watermarks), or if you also want to evade invisible text (which usually can be marked in a PDF viewer and, therefore, interfere with your addition).
The second alternative (using text and image extraction abilities of iText) can be the more appropriate approach in such situations.
Here a sample RenderListener for such a task:
public class FreeSpaceFinder implements RenderListener
{
//
// constructors
//
public FreeSpaceFinder(Rectangle2D initialBox, float minWidth, float minHeight)
{
this(Collections.singleton(initialBox), minWidth, minHeight);
}
public FreeSpaceFinder(Collection<Rectangle2D> initialBoxes, float minWidth, float minHeight)
{
this.minWidth = minWidth;
this.minHeight = minHeight;
freeSpaces = initialBoxes;
}
//
// RenderListener implementation
//
#Override
public void renderText(TextRenderInfo renderInfo)
{
Rectangle2D usedSpace = renderInfo.getAscentLine().getBoundingRectange();
usedSpace.add(renderInfo.getDescentLine().getBoundingRectange());
remove(usedSpace);
}
#Override
public void renderImage(ImageRenderInfo renderInfo)
{
Matrix imageMatrix = renderInfo.getImageCTM();
Vector image00 = rect00.cross(imageMatrix);
Vector image01 = rect01.cross(imageMatrix);
Vector image10 = rect10.cross(imageMatrix);
Vector image11 = rect11.cross(imageMatrix);
Rectangle2D usedSpace = new Rectangle2D.Float(image00.get(Vector.I1), image00.get(Vector.I2), 0, 0);
usedSpace.add(image01.get(Vector.I1), image01.get(Vector.I2));
usedSpace.add(image10.get(Vector.I1), image10.get(Vector.I2));
usedSpace.add(image11.get(Vector.I1), image11.get(Vector.I2));
remove(usedSpace);
}
#Override
public void beginTextBlock() { }
#Override
public void endTextBlock() { }
//
// helpers
//
void remove(Rectangle2D usedSpace)
{
final double minX = usedSpace.getMinX();
final double maxX = usedSpace.getMaxX();
final double minY = usedSpace.getMinY();
final double maxY = usedSpace.getMaxY();
final Collection<Rectangle2D> newFreeSpaces = new ArrayList<Rectangle2D>();
for (Rectangle2D freeSpace: freeSpaces)
{
final Collection<Rectangle2D> newFragments = new ArrayList<Rectangle2D>();
if (freeSpace.intersectsLine(minX, minY, maxX, minY))
newFragments.add(new Rectangle2D.Double(freeSpace.getMinX(), freeSpace.getMinY(), freeSpace.getWidth(), minY-freeSpace.getMinY()));
if (freeSpace.intersectsLine(minX, maxY, maxX, maxY))
newFragments.add(new Rectangle2D.Double(freeSpace.getMinX(), maxY, freeSpace.getWidth(), freeSpace.getMaxY() - maxY));
if (freeSpace.intersectsLine(minX, minY, minX, maxY))
newFragments.add(new Rectangle2D.Double(freeSpace.getMinX(), freeSpace.getMinY(), minX - freeSpace.getMinX(), freeSpace.getHeight()));
if (freeSpace.intersectsLine(maxX, minY, maxX, maxY))
newFragments.add(new Rectangle2D.Double(maxX, freeSpace.getMinY(), freeSpace.getMaxX() - maxX, freeSpace.getHeight()));
if (newFragments.isEmpty())
{
add(newFreeSpaces, freeSpace);
}
else
{
for (Rectangle2D fragment: newFragments)
{
if (fragment.getHeight() >= minHeight && fragment.getWidth() >= minWidth)
{
add(newFreeSpaces, fragment);
}
}
}
}
freeSpaces = newFreeSpaces;
}
void add(Collection<Rectangle2D> rectangles, Rectangle2D addition)
{
final Collection<Rectangle2D> toRemove = new ArrayList<Rectangle2D>();
boolean isContained = false;
for (Rectangle2D rectangle: rectangles)
{
if (rectangle.contains(addition))
{
isContained = true;
break;
}
if (addition.contains(rectangle))
toRemove.add(rectangle);
}
rectangles.removeAll(toRemove);
if (!isContained)
rectangles.add(addition);
}
//
// members
//
public Collection<Rectangle2D> freeSpaces = null;
final float minWidth;
final float minHeight;
final static Vector rect00 = new Vector(0, 0, 1);
final static Vector rect01 = new Vector(0, 1, 1);
final static Vector rect10 = new Vector(1, 0, 1);
final static Vector rect11 = new Vector(1, 1, 1);
}
Using this FreeSpaceFinder you can find empty areas with given minimum dimensions in a method like this:
public Collection<Rectangle2D> find(PdfReader reader, float minWidth, float minHeight, int page) throws IOException
{
Rectangle cropBox = reader.getCropBox(page);
Rectangle2D crop = new Rectangle2D.Float(cropBox.getLeft(), cropBox.getBottom(), cropBox.getWidth(), cropBox.getHeight());
FreeSpaceFinder finder = new FreeSpaceFinder(crop, minWidth, minHeight);
PdfReaderContentParser parser = new PdfReaderContentParser(reader);
parser.processContent(page, finder);
return finder.freeSpaces;
}
For your task you now have to choose from the returned rectangles the one which suits you best.
Beware, this code still may have to be tuned to your requirements:
It ignores clip paths, rendering modes, colors, and covering objects. Thus, it considers all text and all bitmap images, whether they are actually visible or not.
It does not consider vector graphics (because the iText parser package does not consider them).
It is not very optimized.
Applied to this PDF page:
with minimum width 200 and height 50, you get these rectangles:
x y w h
000,000 000,000 595,000 056,423
000,000 074,423 595,000 168,681
000,000 267,304 314,508 088,751
000,000 503,933 351,932 068,665
164,296 583,598 430,704 082,800
220,803 583,598 374,197 096,474
220,803 583,598 234,197 107,825
000,000 700,423 455,000 102,396
000,000 700,423 267,632 141,577
361,348 782,372 233,652 059,628
or, more visually, here as rectangles on the page:
The paper plane is a vector graphic and, therefore, ignored.
Of course you could also change the PDF rendering code to not draw stuff you want to ignore and to visibly draw originally invisible stuff which you want to ignore, and then use bitmap image analysis nonetheless...
EDIT
In his comments the OP asked how to find the rectangle in the rectangle collection returned by find which is nearest to a given point.
First of all there not necessarily is the nearest rectangle, there may be multiple.
That been said, one can choose a nearest rectangle as follows:
First one needs to calculate a distance between point and rectangle, e.g.:
double distance(Rectangle2D rectangle, Point2D point)
{
double x = point.getX();
double y = point.getY();
double left = rectangle.getMinX();
double right = rectangle.getMaxX();
double top = rectangle.getMaxY();
double bottom = rectangle.getMinY();
if (x < left) // point left of rect
{
if (y < bottom) // and below
return Point2D.distance(x, y, left, bottom);
if (y > top) // and top
return Point2D.distance(x, y, left, top);
return left - x;
}
if (x > right) // point right of rect
{
if (y < bottom) // and below
return Point2D.distance(x, y, right, bottom);
if (y > top) // and top
return Point2D.distance(x, y, right, top);
return x - right;
}
if (y < bottom) // and below
return bottom - y;
if (y > top) // and top
return y - top;
return 0;
}
Using this distance measurement one can select a nearest rectangle using code like this for a Collection<Rectangle2D> rectangles and a Point2D point:
Rectangle2D best = null;
double bestDist = Double.MAX_VALUE;
for (Rectangle2D rectangle: rectangles)
{
double distance = distance(rectangle, point);
if (distance < bestDist)
{
best = rectangle;
bestDist = distance;
}
}
After this best contains a best rectangle.
For the sample document used above, this method returns the colored rectangles for the page corners and left and right centers:
EDIT TWO
Since iText 5.5.6, the RenderListener interface has been extended as ExtRenderListener to also be signaled about Path construction and path drawing operations. Thus, the FreeSpaceFinder above could also be extended to handle paths:
//
// Additional ExtRenderListener methods
//
#Override
public void modifyPath(PathConstructionRenderInfo renderInfo)
{
List<Vector> points = new ArrayList<Vector>();
if (renderInfo.getOperation() == PathConstructionRenderInfo.RECT)
{
float x = renderInfo.getSegmentData().get(0);
float y = renderInfo.getSegmentData().get(1);
float w = renderInfo.getSegmentData().get(2);
float h = renderInfo.getSegmentData().get(3);
points.add(new Vector(x, y, 1));
points.add(new Vector(x+w, y, 1));
points.add(new Vector(x, y+h, 1));
points.add(new Vector(x+w, y+h, 1));
}
else if (renderInfo.getSegmentData() != null)
{
for (int i = 0; i < renderInfo.getSegmentData().size()-1; i+=2)
{
points.add(new Vector(renderInfo.getSegmentData().get(i), renderInfo.getSegmentData().get(i+1), 1));
}
}
for (Vector point: points)
{
point = point.cross(renderInfo.getCtm());
Rectangle2D.Float pointRectangle = new Rectangle2D.Float(point.get(Vector.I1), point.get(Vector.I2), 0, 0);
if (currentPathRectangle == null)
currentPathRectangle = pointRectangle;
else
currentPathRectangle.add(pointRectangle);
}
}
#Override
public Path renderPath(PathPaintingRenderInfo renderInfo)
{
if (renderInfo.getOperation() != PathPaintingRenderInfo.NO_OP)
remove(currentPathRectangle);
currentPathRectangle = null;
return null;
}
#Override
public void clipPath(int rule)
{
// TODO Auto-generated method stub
}
Rectangle2D.Float currentPathRectangle = null;
(FreeSpaceFinderExt.java)
Using this class the result above is improved to
As you see the paper plane and the table background colorations now also are taken into account.
My other answer focuses on the original question, i.e. how to find free space with given minimum dimensions on a page.
Since that answer had been written, the OP provided code trying to make use of that original answer.
This answer deals with that code.
The code has a number of shortcoming.
The choice of free space on a page depends on the number of pages in the document.
The reason for this is to be found at the start of the loop over the pages:
for(int i = 1; i <= n; i++)
{
Collection<Rectangle2D> rectangles = find(reader, 300, 100, n, stamper);
...
The OP surely meant i, not n there. The code as is always looks for free space on the last document page.
The rectangles are lower than they should be.
The reason for this is to be found in the retrieval and use of the rectangle coordinates:
x = (float) best.getX();
y = (float) best.getY();
...
getFooterTable(i, n).writeSelectedRows(0, -1, x, y, stamper.getOverContent(i));
The Rectangle2D methods getX and getY return the coordinates of the lower left rectangle corner; the PdfPTable methods writeSelectedRows, on the other hand, require the upper left rectangle corner. Thus, getMaxY should be used instead of getY.
I have a region in my JPanel bounded by the point (0,0) and (width,height). It is a square.
I have a word
String s;
I'd like to find the maximum font size that I can use for s. Now, I know there is a way to do it using FontMetrics and making a for loop to keep increasing the size of the font until it doesn't fit inside the region. But this is SO inefficient and there must be a way to compute the font size of a given font type, such as "Courier" that will fit in this region.
Example of BAD way:
Font f = new Font("Courier", Font.PLAIN, 1);
FontMetrics fm = this.getFontMetrics(f); //this is a JPanel
do {
f = new Font("Courier", Font.PLAIN, f.getSize()+1);
fm = this.getFontMetrics(f);
while(fm.stringWidth(s) < width && fm.getHeight() < height);
I had the same problem and found a solution that is a little bit optimized, compared to just iterating over all font sizes. I try to converge towards the optimal font size by adjusting diffs that I either add or subtract until I find a diff font size below 1.
Graphics2D graphics = image.createGraphics();
graphics.setColor(Color.black);
if (subtitleFont == null) {
//create rectangle first (from a separate library
int[] rect = matrix.getEnclosingRectangle();
// define the maximum rect for the text
Rectangle2D maxRect = new Rectangle2D.Float(0, 0, w - 7, h - rect[0] - rect[3] - 10);
subtitleX = 0;
subtitleY = 0;
// starting with a very big font due to a high res image
float size = 80f * 4f;
// starting with a diff half the size of the font
float diff = size / 2;
subtitleFont = graphics.getFont().deriveFont(Font.BOLD).deriveFont(size);
FontMetrics fontMetrics = graphics.getFontMetrics(subtitleFont);
Rectangle2D stringBounds = null;
while (Math.abs(diff) > 1) {
subtitleFont = subtitleFont.deriveFont(size);
graphics.setFont(subtitleFont);
fontMetrics = graphics.getFontMetrics(subtitleFont);
stringBounds = fontMetrics.getStringBounds(options.subtitle, graphics);
stringBounds = new Rectangle2D.Float(0f, 0f, (float) (stringBounds.getX() + stringBounds.getWidth()), (float) ( stringBounds.getHeight()));
if (maxRect.contains(stringBounds)) {
if (0 < diff) {
diff = Math.abs(diff);
} else if (diff < 0) {
diff = Math.abs(diff) / 2;
}
} else {
if (0 < diff) {
diff = - Math.abs(diff) / 2;
} else if (diff < 0) {
if (size <= Math.abs(diff)) {
diff = - Math.abs(diff) / 2;
} else {
diff = - Math.abs(diff);
}
}
}
size += diff;
}
subtitleX = (int) ((w/2) - (stringBounds.getWidth() / 2));
subtitleY = (int) (h - maxRect.getHeight() + fontMetrics.getAscent());
}
graphics.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
graphics.drawString(options.subtitle, subtitleX, subtitleY);
I have tried that with different resolutions of the image and the sizes of the font. It takes 10 to 12 iterations until a font is found that will fit the max rectangle. I hope it will be helpful to somebody.
yes, I met the same problem as well, and I know what's your meaning of 'inefficient'.
I tried a solution that measuring the unit count for a string by font size: 1 (default).
for example:
String line = "This is a test";
Font font = Font.createFont(Font.TRUETYPE_FONT, new File("/var/fonts/times.ttf"));
FontRenderContext ctx = new FontRenderContext(font.getTransform(), false, false);
Rectangle2D rect = font.getStringBounds(line, ctx);
BigDecimal widthUnits = BigDecimal.valueof(rect.getWidth());
then, you get the widthUnits of line by font size 1. if it divided by region width and reserve the integer part (round down), you'll the the max font size in horizontally.
int maxSizeHor = BigDecimal.valueOf(width)
.divide(widthUnits, 1, BigDecimal.ROUND_DOWN)
.intValue();
But, it's not enougth. you should also calculate the max font size in vertically. Fortunately, each line with the same font style and font size has the same height. if there are multiple lines, you can use:
lines.length * each height in font size 1.
such as the following:
String[] lines = new String{"This is a test", "Hello World!"};
BigDecimal heightUnits = BigDecimal.valueOf(rect.getHeight())
.multiply(BigDecimal.valueOf(lines.length));
int maxSizeVer = BigDecimal.valueOf(height)
.divide(heightUnits
.multiply(BigDecimal.valueOf(lines.length)),
1,BigDecimal.ROUND_DOWN)
.intValue();
Finally, compare and fetch the minium value as the maximum font size:
Math.min(maxSizeHor, maxSizeVer)
But, I met another problem: the single char 'i' as input string at font size:1, you will get the the width units: 0.0 . However, in actually, it won't be zero though it's a very tiny value. so I set 1000 as default font size, and divide 1000 after each progress. then I get the non-zero value.