I work on a project where I need to constantly get bitmaps and draw them on a picturebox.
The idea is to draw a first initial bitmap, then retrive the rest of the bitmap and draw them above the initial one. (The first one still displayed in the picturebox, so I want to draw them on the first bitmap).
I tried to design a custom control, to implement the OnPaint event, but the second time the event is fired, it draws the second block and completely conceals the image which had been drawn before.
public class RapidPictureBox: PictureBox
{
public pictureBox1Control()
{
SetStyle(
ControlStyles.AllPaintingInWmPaint |
ControlStyles.OptimizedDoubleBuffer |
ControlStyles.UserPaint |
ControlStyles.ResizeRedraw, true);
}
public Bitmap block = null;
public int x = 0, y = 0;
protected override void OnPaint(PaintEventArgs e)
{
e.Graphics.DrawImage(block, x, y);
}
}
private void Form1_Load(object sender, EventArgs e)
{
RapidPictureBox pictureBox1 = new RapidPictureBox();
pictureBox1.Dock = DockStyle.Fill;
Controls.Add(pictureBox1);
pictureBox1.block = new Bitmap("3.png"); //first initial image
pictureBox1.block = new Bitmap("2.png"); //draw on the initial one.
}
I'm not sure what's wrong in the code. I use the e EventArgs to draw a new block everytime I need but it seems the new drawing compeletly hides the previous bitmap.
you can create a graphics object from the picturebox,then redraw it over the current image
initial =new Bitmap("test.png");
pictureBox1.Image = initial;
var graphics = pictureBox1.CreateGraphics(); //create a graphic objec
graphics.DrawImage(block, x,y);//that's the second method
What you should do is overlay the new image on previous image.
Let's say there is a primary image (first image) and you want to print next image(overlapping image) on that same primary image. Use following method to do that.
private Bitmap GetOvelappedImages(Bitmap primaryImage, Bitmap overlappingImage)
{
//create graphics from main image
using (Graphics g = Graphics.FromImage(primaryImage))
{
//draw other image on top of main Image
g.DrawImage(overlappingImage, new Point(0, 0));
}
return primaryImage;
}
then set this new image to pictureBox1.block.
private void Form1_Load(object sender, EventArgs e)
{
RapidPictureBox pictureBox1 = new RapidPictureBox();
pictureBox1.Dock = DockStyle.Fill;
Controls.Add(pictureBox1);
pictureBox1.block = GetOverlappedImages(new Bitmap("3.png"),new Bitmap("2.png")); //draw on the initial one.
}
That should work for you.
Note: You should dispose images after they are used.
Update:
You need to redraw whole image because, OnPaint is called only when current image shown on picture box needs to be redrawn.
The OnPaint method is overridden to repaint the image each time the form is painted; otherwise the image would only persist until the next repainting.
Read documentation for OnPaint here
The problem with your code is that you are not adding pictures to the control you are replacing them.
Side Note: With the code you have you are not disposing of the Bitmap objects set in the PictureBoxes image and so this could cause memory leaks.
You can create a similar control LayeredPictureBox. This will get all of the images and draw them on top of each other. It will have poor performance and the images will need to have transparency to look layered but you get the idea:
public class LayeredPictureBox : PictureBox
{
public LayeredPictureBox()
{
SetStyle(
ControlStyles.AllPaintingInWmPaint |
ControlStyles.OptimizedDoubleBuffer |
ControlStyles.UserPaint |
ControlStyles.ResizeRedraw, true);
}
public List<Bitmap> blocks = new List<Bitmap>();
public int x = 0, y = 0;
protected override void OnPaint(PaintEventArgs e)
{
foreach (Bitmap block in blocks)
{
e.Graphics.DrawImage(block, x, y);
}
}
}
private void Form1_Load(object sender, EventArgs e)
{
RapidPictureBox pictureBox1 = new RapidPictureBox();
pictureBox1.Dock = DockStyle.Fill;
Controls.Add(pictureBox1);
pictureBox1.blocks.Add(new Bitmap("3.png")); //first initial image
pictureBox1.blocks.Add(new Bitmap("2.png")); //draw on the initial one.
}
Another option is to merge all of the images together on adding them and then just drawing that image into the PictureBox.
Related
I made several drawings using Windows forms application visual studio Bitmap, my goal is to clear all drawings when I press the push button (make the background clear)
The Following code is not exactly what my original code but this is how I created each drawing
Rectangle area;
Bitmap creature;//this only one drawing but I have several
Graphics scG;
Bitmap background;
private void Form1_Load(object sender, EventArgs e)
{
background = new Bitmap(Width, Height);
area = new Rectangle(50, 50, 50, 50);
creature = new Bitmap(#"C:\Users\Desktop\Image.png");
}
public Bitmap Draw()
{
Graphics scG = Graphics.FromImage(background);
scG.DrawImage(creature, area);
return background;
}
}
private void Button_Click(object sender, EventArgs e)
{
// I want to clear all the drawings by push this button
}
There is no way to remove things drawn on a bitmap.
Why don't just dump the old background bitmap and create a new one?
this is duplicate , see this link :
How to delete a drawn circle in c# windows form?
or test these Code :
Graphics.Clear();
or
Control.Invalidate();
or
this.Invalidate();
The real way is to use event Paint:
private void Form1_Paint(object sender, PaintEventArgs e)
{
e.Graphics.DrawImage(creature, area); // draw your image here...
}
To delete, just do nothing in Form1_Paint, and call Refresh();
I want to create a custom control or override the pictuebox's onpaint event such that i get access to the image before its drawn in the picturbox,so that i can rotate the image.
I know that i can do something like this
private void pictureBox1_Paint(object sender, PaintEventArgs e) {
e.Graphics.DrawRectangle(Pens.Black, new Rectangle(10, 10, 20, 20));
}
How to get access to the image and how to create a custom control.
Here is a quick example of a subclass: It hides the original Image property and replaces it with one that does a rotation before assigning it:
class RotatedPictureBox : PictureBox
{
private Image image;
public new Image Image {
get { return image; } // ?? you may want to undo the rotation here ??
set {
Bitmap bmp = value as Bitmap ;
// use the rotation you need!
if ( bmp != null ) bmp.RotateFlip(RotateFlipType.Rotate270FlipX);
image = bmp;
base.Image = Image;
}
}
}
public RotatedPictureBox ()
{
}
}
Caveat: Assigning an Image seems to work but I didn't test it for all possible uses.. Known limitations
It doesn't rotate images assigned via ImageLocation.
I had a crash once, when assigning an image in the Designer, but can't reproduce.
I'm trying to build a little test application (and my WinForm skills have rusted somewhat) with an Image and some overlays on top of it.
My image is set to stretch in the PictureBox but my fields on the right hand side I want to be from the origin of the image. Therefore I decided to render directly on the image that the PictureBox is using to ensure that the co-ordinates are always correct. Here's the white box rendering:
private void pbImage_Paint(object sender, PaintEventArgs e)
{
try
{
if (this.rdFront.Checked)
RenderFront(pbImage.Image, true);
else
RenderBack(pbImage.Image, true);
}
catch (ArgumentNullException ex)
{ }
}
public void RenderFront(Image image, bool includeBoxes)
{
// If we have no image then we can't render
if (image == null)
throw new ArgumentNullException("image");
Graphics gfx = Graphics.FromImage(image);
// Get the top label
foreach (MessageConfiguration config in this.config.Values.Where(c => c.Front))
{
if (includeBoxes)
{
// Fill a White rectangle and then surround with a black border
gfx.FillRectangle(Brushes.White, config.X, config.Y, config.Width, config.Height);
gfx.DrawRectangle(Pens.Black, config.X - 1, config.Y - 1, config.Width + 2, config.Height + 2);
}
gfx.DrawString(config.Text, new Font(FontFamily.GenericMonospace, config.FontSize), Brushes.Black, new PointF(config.X, config.Y));
}
}
The problem that I've got is if I do this and always draw on the underlying image then when I move the white overlay, I end up with un-drawn parts of the image. So I decided to clone the image before each re-render (on the basis that I don't care about performance).
I therefore decided to clone the image whenever I need to manually invalidate it, and call this when a setting changes:
public void Refresh()
{
if (this.rdFront.Checked)
pbImage.Image = new Bitmap(front);
else
pbImage.Image = new Bitmap(back);
this.pbImage.Invalidate();
}
Now I'm sure I must be missing something obvious - if I modify one of the values my penguins render with no overlay. However if I force a resize of the application then both the penguins and the overlay suddenly appear.
Can anyone suggest what I might be doing wrong?
Edit
Here's a download link to the project as it's quite small. Paste a path to an image in the 'Front Image' box and try using the controls on the right (set 100x100 height and width). Try re-sizing to see the desired affect. https://dl.dropboxusercontent.com/u/41796243/TemplateTester.zip
Controls and Forms have a Refresh method already. Are you really calling your Refresh method? Aren't you getting a warning that you should use the new keyword? Better give your Refresh method another name (e.g RefreshImage)!
I'm really not sure why you are using a picture box but then decide to do your on painting. I suggest to draw to an image off-screen and then simply assign it to the picture box:
public void RefreshImage()
{
Bitmap bmp;
if (this.rdFront.Checked)
bmp = new Bitmap(front);
else
bmp = new Bitmap(back);
using (Graphics gfx = Graphics.FromImage(bmp)) {
foreach (MessageConfiguration config in this.config.Values.Where(c => c.Front))
{
if (includeBoxes) {
// Fill a White rectangle and then surround with a black border
gfx.FillRectangle(Brushes.White, config.X, config.Y, config.Width, config.Height);
gfx.DrawRectangle(Pens.Black, config.X - 1, config.Y - 1, config.Width + 2, config.Height + 2);
}
gfx.DrawString(config.Text, new Font(FontFamily.GenericMonospace, config.FontSize), Brushes.Black, new PointF(config.X, config.Y));
}
}
pbImage.Image = bmp;
}
and remove the pbImage_Paint method.
Another possibility is to use the pbImage_Paint event handler in another way. Call the base.Paint() handler of the picture box that draws the image but leave the image itself unchanged. Instead draw on top of it by using the Graphics object given by the PaintEventArgs e argument. This Graphics object represents the client area of the picture box. This does not alter the Bitmap assigned to the picture box, but only draws on the screen.
private void pbImage_Paint(object sender, PaintEventArgs e)
{
base.Paint(); // Paints the image
if (this.rdFront.Checked)
RenderFront(e.Graphics, true);
else
RenderBack(e.Graphics, true);
}
public void RenderFront(Graphics g, bool includeBoxes)
{
foreach (MessageConfiguration config in this.config.Values.Where(c => c.Front)) {
if (includeBoxes) {
g.FillRectangle(Brushes.White, config.X, config.Y, config.Width, config.Height);
g.DrawRectangle(Pens.Black, config.X - 1, config.Y - 1, config.Width + 2, config.Height + 2);
}
g.DrawString(config.Text, new Font(FontFamily.GenericMonospace, config.FontSize), Brushes.Black, new PointF(config.X, config.Y));
}
}
How to do Free hand Image Cropping in C# window application??
Okay, you provided very small amount of information, but I'll assume that you are using winforms. There are some tasks dealing with freehand-technique such as:
Drawing
Drag-n-dropping
Cropping
Selecting
They all are very similar. Let's assume that you have a PictureBox and want to crop an image inside it.
// Current selection
private Rectangle _cropRectangle;
// Starting point
private Point _cropStart;
// Dragging flag
private bool _isDragging;
private void pBox_MouseDown(object sender, MouseEventArgs e)
{
_cropRectangle = new Rectangle(e.X, e.Y, 0, 0);
_isDragging = true;
}
private void pBox_MouseUp(object sender, MouseEventArgs e)
{
_isDragging = false;
}
private void pBox_MouseMove(object sender, MouseEventArgs e)
{
if (!_isDragging)
return;
_cropRectangle = new Rectangle(Math.Min(_cropStart.X, e.X),
Math.Min(_cropStart.Y, e.Y),
Math.Abs(e.X - _cropStart.X),
Math.Abs(e.Y - _cropStart.Y));
pBox.Invalidate();
}
private void pBox_Paint(object sender, PaintEventArgs e)
{
e.Graphics.DrawRectangle(Pens.Red, _cropRectangle);
}
What happens: I make use of three mouse events (MouseDown, MouseUp, MoseMove) and the Paint event. Basically, whenever you want to do anything from the above list, you'll have handle these four events.
I tried to keep the code short and self-explanatory. There are four event handlers working with three instance fields. The fields are used to store the current state of dragging process.
Feel free to customize the code, especially the pBox_Paint handler. Mine just draws a thin red rectangle around selected area. You might want to do something more elaborate here.
Whenever you're done with your rectangle, you can call the Crop method:
private Image Crop()
{
Bitmap croppedImage = new Bitmap(_cropRectangle.Width, _cropRectangle.Height);
using (Graphics g = Graphics.FromImage(croppedImage))
{
g.DrawImage(pBox.Image, 0, 0, _cropRectangle, GraphicsUnit.Pixel);
}
return croppedImage;
}
It creates a new Bitmap and put the selected portion of source image into it. The returned Image object might be used in any manner you like.
EDIT: trying to simplify the code I made some mistakes earlier, fixed now.
You can use Graphics.DrawImage to draw a cropped image onto the graphics object from a bitmap.
Rectangle cropRect = new Rectangle(...);
Bitmap src = Image.FromFile(fileName) as Bitmap;
Bitmap target = new Bitmap(cropRect.Width, cropRect.Height);
using(Graphics g = Graphics.FromImage(target))
{
g.DrawImage(src, cropRect,
new Rectangle(0, 0, target.Width, target.Height),
GraphicsUnit.Pixel);
}
You can also refer the full code for this....
Refer this *Link*
I have a problem:
I have 3 picture boxes with 3 different images as in Image
what can i set to pictureBox3 so both images look same.....
EDITED:
I want to move pictureBox3 on pictureBox2,
So there is no Option to merge them to single image
Make sure the image in pictureBox3 is transparent. Set the BackColor to transparent. In code, set the Parent property of the pictureBox3 to be pictureBox2. Adjust the Location coordinates of pictureBox3 since they will be relative to the coordinates of pictureBox2 once you've changed the Parent.
private void Form1_Load(object sender, EventArgs e)
{
pictureBox3.Parent = pictureBox2;
pictureBox3.Location =
new Point(
pictureBox3.Location.X
- pictureBox2.Location.X,
pictureBox3.Location.Y
- pictureBox2.Location.Y);
}
In designer you will not see the transparency, but at runtime you will.
Update
In the image, the left side shows the designer view, the right side is the runtime version.
Another update
I really don't understand how it would be possible that this doesn't work for you. I suppose there must be something we are doing different. I'll describe the exact steps to take to create a working sample. If you follow the exact same steps, I wonder if we'll get the same results or not. Next steps describe what to do and use two images I found on the net.
Using Visual Studio 2008, create a New Project using template Windows Forms Application. Make sure the project is targeted at the .NET Framework 3.5.
Set the Size of the Form to 457;483.
Drag a PictureBox control onto the form. Set its Location to 0;0 and its Size to 449;449.
Click the ellipsis besides its Image property, click the Import... button and import the image at http://a.dryicons.com/files/graphics_previews/retro_blue_background.jpg (just type the URL in the File name text box and click Open). Then click OK to use the image.
Drag another PictureBox onto the form, set its Location to 0;0 and its Size to 256;256. Also set its BackColor property to Transparent.
Using the same method as described above, import image http://www.axdn.com/redist/axiw_i.png which is a transparent image.
Now place the following code in the form's OnLoad event handler:
private void Form1_Load(object sender, EventArgs e)
{
pictureBox2.Parent = pictureBox1;
}
That's it! If I run this program I get a transparent image on top of another image.
I'll add another example that according to the updated requirement allows for moving image3.
To get it working, put an image with transparency in Resources\transp.png
This uses the same image for all three images, but you can simply replace transparentImg for image1 and image2 to suitable images.
Once the demo is started the middle image can be dragged-dropped around the form.
public partial class Form1 : Form
{
private readonly Image transparentImg; // The transparent image
private bool isMoving = false; // true while dragging the image
private Point movingPicturePosition = new Point(80, 20); // the position of the moving image
private Point offset; // mouse position inside the moving image while dragging
public Form1()
{
InitializeComponent();
//
// pictureBox1
//
this.pictureBox1.Location = new System.Drawing.Point(0, 0);
this.pictureBox1.Name = "pictureBox1";
this.pictureBox1.Size = new System.Drawing.Size(231, 235);
this.pictureBox1.TabIndex = 0;
this.pictureBox1.TabStop = false;
this.pictureBox1.Paint += new System.Windows.Forms.PaintEventHandler(this.pictureBox1_Paint);
this.pictureBox1.MouseDown += new System.Windows.Forms.MouseEventHandler(this.pictureBox1_MouseDown);
this.pictureBox1.MouseMove += new System.Windows.Forms.MouseEventHandler(this.pictureBox1_MouseMove);
this.pictureBox1.MouseUp += new System.Windows.Forms.MouseEventHandler(this.pictureBox1_MouseUp);
this.Controls.Add(this.pictureBox1);
transparentImg = Image.FromFile("..\\..\\Resources\\transp.png");
}
private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
var g = e.Graphics;
g.DrawImageUnscaled(transparentImg, new Point(20, 20)); // image1
g.DrawImageUnscaled(transparentImg, new Point(140, 20)); // image2
g.DrawImageUnscaled(transparentImg, movingPicturePosition); // image3
}
private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
{
var r = new Rectangle(movingPicturePosition, transparentImg.Size);
if (r.Contains(e.Location))
{
isMoving = true;
offset = new Point(movingPicturePosition.X - e.X, movingPicturePosition.Y - e.Y);
}
}
private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
if (isMoving)
{
movingPicturePosition = e.Location;
movingPicturePosition.Offset(offset);
pictureBox1.Invalidate();
}
}
private void pictureBox1_MouseUp(object sender, MouseEventArgs e)
{
isMoving = false;
}
}
This code will do the trick:
using (Graphics g = Graphics.FromImage(pictureBox1.Image))
{
g.DrawImage(pictureBox2.Image,
(int)((pictureBox1.Image.Width - pictureBox2.Image.Width) / 2),
(int)((pictureBox1.Image.Height - pictureBox2.Image.Height) / 2));
g.Save();
pictureBox1.Refresh();
}
It will draw the image from pictureBox2 on the existing image of pictureBox1.
For starters, set the BackColor property of PictureBox3 to Transparent. This should work in almost all cases.
You should also use an image with a transparent background instead of white so you do not have the white borders around your purple circle. (Recommended image format: PNG)
Update
Following the replies I got, it appears setting the BackColor to Transparent doesn't work. In that case, it's best you handle the Paint event of the PictureBox and do the painting of the new image yourself as Albin suggested.
You might do some hack by overriding OnPaint and stuff, example here.
But I'd recommend to merge the pictures in pictureBox2 and 3 into a single image before displaying them in a single pictureBox.