Hi, I'm using Graphics.DrawLines (Pen, PointF[]) to draw a long curve with thousands of points - works perfectly on printers. Now I have found, that the preview functionality seems to have problems, if I pass more than 6000 or 7000 points. Now I'm a bit concerned, that there are different ...more >>

Hi everybody, I encounter a problem when painting a window in two programmatically different applications that should display the same kind of picture. The picture consists of a bitmap on whose top there appears an icon. The problem is that in one app the picture is always stable, while in th...more >>

I tryed to do a bitmap export in my app by creating a bitmap, drawing to it and saving the file. Something like that void SaveToFile(string pngfile) { using(Bitmap bmp = new Bitmap(200, 200); { using(Graphics g = Graphics.FromImage(bmp)) g.DrawString("Hello!", ...more >>

In my .NET application I have some text rendered through GDI. It draws and print nicely. Now I would like to implement image export. So I create a new System.Drawing.Bitmap(width, height) then I create a Graphic g = Graphics.FromImage(bmp) then I use HDC hdc = g.GetHdc(); and use ExtTextOu...more >>

Hello! I am creating a user control with several methods, each method should draw something in my user control; from a winform, I should use: myControl.ShowBands or myControl.ShowLabels, etc.; but I don't know how to do that, because all the logic to draw should be in the Paint event, but each ...more >>

How do you clear an image in a Picturebox control? Do you simply set it to nullptr? ie: pictureBox1->Image = nullptr; Do you have to rely on the garbage collector or can you deterministicly release the memory associated with the image?...more >>

How do you convert a 24-bit color image into a 256-shades-of-gray image? Thanks, Shawn ...more >>

Hi, i sent image byte via bt from j2me phone to c# application, after i have to create image using this code: .... byte[] pixels .... Bitmap bmp = new Bitmap(160, 120, PixelFormat.Format8bppIndexed); BitmapData d = bmp.LockBits(new Rectangle(0, 0, 160, 120), ImageLockMode.WriteOnly, Pi...more >>

Hi all We are working on a large project. Main functionality is accessing database with ado.net. A small corner of the project contains some graphics (Bitmaps) analysis. We all know a lot about ADO.Net but not so much about graphics. So I hope this newsgroups can point us to the right way. By ...more >>

I have a problem when using Bitmap in PictureBox. I have been using several PixelFormats without problems but when I tried to use Format16bppGrayScale I got an exception = "Parameter is not valid" Here's the very simplified code: Bitmap bmp = new Bitmap(100, 100, PixelFormat....more >>

I have found a possible error in the PaperSource class in the .NET framework v1.1. The possible error lies in the Kind-property, if the Kind value exceeds 257, then it just returns 257. It looks like this : --- hp color LaserJet 2550 PCL 6 --- "Kind", "Name" 15 Automatically Select ...more >>

The PaperSource class is used to define trays on printers, which is quite nice, untill I found an error in it, \\DGM-SDG-AD1\hp color LaserJet 2550 PCL 6 15 Automatically Select 261 Printer Auto Select 260 Manual Feed in Tray 1 259 Tray 1 258 Tray 2 1272 Uns...more >>

Hi, I am using Bob's primitive class to render objects on the screen, and perform hit tests to see if the mouse moves over any object (code below). Public Overridable Function HitTest(ByVal p As Point) As Boolean Return (New Rectangle(Me.m_Location, Me.m_Size)).Contains(p) End Functi...more >>

The following is a snippet right out of the LockBits help: IntPtr ptr = bmpData->Scan0; .... .... // Copy the RGB values into the array. System::Runtime::InteropServices::Marshal::Copy( ptr, rgbValues, 0, bytes ); // Set every red value to 255. for ( int counter = 0;...more >>

hi, i am using a color matrix to change the brightness and contrast of a bitmap, but i can't make the black color stay black when changing the brightness. is it impossible since changing the brightness is adding the same number to the R,G and B? if it's possible, how do i do it? tha...more >>

***Please let me know if this is the correct forum for this question. I am having problems with a picture box as follows: I have an asynchronous WinForm application that communicates with an ASCII based text radio and saves data to a database. The 'guts' of the functionality have all been w...more >>

In one of my view I should do precision rendering. Each character, string, etc.. should be at a particular, WYSIWIG position in Inches. To achieve this quality when drawing I set the Page's unit to be Inch, like that: ==>>> e.Graphics.PageUnit = GraphicsUnit.Inch; Now my problem is I shoul...more >>

Does anyone have any recommendations on a 3rd party component (COM or .Net component) that I can plug into my solution that'll provide basic image functionality (e.g. croping, pasting, resize, multi-format support jpg/tif/gif,etc)? Thanks very much!...more >>

I am using .NET 2.0 and building a custom control. There are multiple graphics elements that I would like to render on the surface. When drawn together they form the complete control image but need to be managed separately because they might have different scale, units, move indendently, a...more >>

With this code: Font f = new Font("Microsoft Sans Serif",20 ); LOGFONT lf = new LOGFONT(); f.ToLogFont(lf); Font newFont; newFont = Font.FromLogFont(lf); f and newFont are not the "same" .Net Font. Can anyone comment on this? ...more >>

Hi, I'm trying to hit-test a rectangle thats been rotated 45 degrees, however the IsVisible and IsOutlineVisible don't appear to take the transformation into account. Does anyone know of a solution? I don't want to manually rotate the Point I'm passing in because I don't know if the obje...more >>

I save a set of subsampled images to display when the user zooms into a map. At runtime I draw a circle around a point-of -interest in the image (Graphics.DrawEllipse). If I use ImageFormat.Jpeg for the resulting image, the¨ image is OK but the circle is blurred which is natural in jpeg. If ...more >>

Hi, I have a free (grin) third party component I am working with which has a Print() method. The gotcha is that it prints only to the default printer; it doesn't give me the ability to indicate what printer to use. I am semi-new to ..Net and for the life of me I can't figure out how to designa...more >>

is there a way (like you can do with a web site table) to take an image and repeat it along the X axis of a given rectangle? thanks! ...more >>

(I'm going to try in this newsgroup; nobody in the VB group seems to answer my imaging questions over there) Can someone tell me why setting the opacity of a control in 2005 no longer works like it did in 2003 (using Color.FromArgb)? In 2003, I could make the opacity of the text of a Label ...more >>

Hello! I have a webpage (FW1.1) in which some heavy drawing takes place (code behind). In some cases I call the DrawPath(...) function 20 000-30 000 times. This works well everywhere except in one environment. The time to draw the geometries is about 20-30 times higher than everywhere else....more >>

Hello, I am experiencing lot of problem with BufferedGraphics rendering. In on paint of my control I do: float xOffset = ComputeXOffsetSomehow(); float yOffset = ComputeYOffsetSomehow(); BufferedGraphicsContext doubleBufferContext = BufferedGraphicsManager.Current; BufferedGraphics backBu...more >>

Hello, I need to convert a monochrome BMP according to the format specified below. This needs to be done in compact framework 2.0. The format needed: To represent the 16x16 square box, the data (shown in boldface) is as follows. bytes bits HEX BINARY FF FF 1111111111111111 80 01...more >>

I have a BITMAP, say it's w=200 x h=100 pixels. I have a rectangle *which has a border* of 3 pixels. (It is not necessarily all contained in the bitmap. Let say the rectangle is x= -1, y=50, w=100, h=100 (with a border=3) I want : 1. to store in memory all the pixels that are covered by the...more >>

I have implemented a custom PictureBox as Bob Powell instructs (thanks for your code!) using a Matrix transformation in the OnPaint method. Im trying to scroll the image dragging it with the mouse. The mousemove event =ECs captured moving the scrollsbar accordingly. This works ok in a non-zoom...more >>

Hi I'm working on making a TreeView and re-doing the painting myself, but I'm having a problem with this code: private VisualStyleRenderer glyphOpen = new VisualStyleRenderer(VisualStyleElement.TreeView.Glyph.Opened); and any code similar... for some reason whenever those lines are decla...more >>

Hello Bob powell, I have seen you solving problem of many peoples, so i hope you can also solve my problem. Well I am trying to Make a program to print the ID cards.In the window form i have two picture box, one is for the photo of the students and one to hold the signature of the Prin...more >>

Hello: Does somebody know what the best control for drawing on ? Thank you, dave ...more >>

I'm taking a rectangle and using a Matix and GraphicsPath to draw it rotated about its upper left corner. The problem is GraphicsPath.Transform changes the upper left point in the path slightly, so that it is no longer the same as m_rectanglef.Location. This is especially a problem when m_...more >>

I have to do some WYSIWIG rendering. Because I need to know exactly where is what and have to have the same output on both the screen and the printer I decided to change my Page unit to Inches. As I was testing my first thought was to draw red outline of some relevant rectangle. And here ...more >>

I have to do some WYSIWIG rendering. Bacause I need exactly where is what and have the same output on the printer I decided to change my Page unit to Inch. As I was testing my first though was to draw read outline of some relevant rectangle. And here I had my 1st encouter with those infamou...more >>

Hello, If I Response.Write("hello") before I image2.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Gif) then I see miscellaneous characters where the image should be. When I reverse the order of the statements above then I don't see the text at all. Is there...more >>

Hello, Is it possible to change the colorpalette of a GIF image without using Lockbits ? I'm doing the following : 1 - load any bitmap 2 - save as GIF (MS GDI+ saves using its default half tone palette) 3 - load this just created image 4 - retrieve the colorpalette 5 - change an entry...more >>

I have a problem when using Gdiplus Bitmap::Save: I can't save the bitmap back to the file from which the Bitmap object is constructed. I learned from Bob Powell's Gdi+ Faq that there is a solution in C# to this problem, but right now I'm programming with VC++, and I don't want to program with m...more >>

Hello: I have application that displays graph as line. Data that feeds this graph is updated every 1 Sec. Q1: What the best way to accomplish this task ? Q2: The same questions when graph is a sequence of rectangles? I'm new to this subject but i beleive its old topic. Does somebody...more >>

Hi guys, - I'm trying to load some jpeg's and 1 frame tiff's to bitmaps. Done! I use the Bob Powell GDI+ method (http://www.bobpowell.net/generating_multipage_tiffs.htm) and everything seems ok, but, when look closely i found that all the pages loaded from .jpg's files, doesn't respect the re...more >>

Hi all. I am creating an windows app in Framework 2.0, which has to draw a risk matrix based on data supplied by users. I wouldn't like to do it from the scratch, so I am looking for some library, which could help me. Does anybody know some library designed to drawing risk matrixes? If no...more >>

Hello I am having curious problem with Graphics.TranslateTransform. My OnPaint handler in my custom control (derived directly from Control) basically has the following form: DrawWithVisualStyle( pe.Graphics ); pe.Graphics.TranslateTransform( ... ); DrawConte...more >>

VS 2005 Just for the recreation of it, and to 'refresh,' my mental .NET drawing buffer, I wrote some code that moves a medium-large .jpg (4472,1360, 24bps) around on a 1024x768 monitor. I put a PictureBox on the Form and set its Image property to the bitmap as an imported resource. I use...more >>

Hi all I'm looking for a way to find a color of the surface of a control at a given point. ie: Dim re as Rectangle = Me.ClientRectangle dim co as Color = GetColorAt(re, New Point(0, 0)) 'This finds the color in the upper left corner of the control Any idea for GetColorAt? Thank you...more >>

Hi I am developing a heatmap-component, and I need to define the color of each pixel individually. How do I do that most effeiciently? I cant seem to find a way to draw individual pixels, short of creating 1x1 line or rectangle-objects. Is that the way to go, or am I missing somethin...more >>

Hi all - I have 8 images (maps) that I need to load into a picture box and then based on a button pressed, animate them (like what happens on this site http://www.goes.noaa.gov/GSSLOOPS/wcwv.html) How do I do that? The Imagelist/Timer does not work as the imagelist only can take images up to...more >>

I have a control that shrinks and grows depeding on the user's actions (similar to the toolbox when unpinned in VS). When the control is docked to the top or left, it works perfectly. But when it is docked to the bottom or right, it doesn't. You can see the form distinctly resize the control ...more >>

I want to upload a TIFF Picture which I created with mspaint.exe (just opened a jpeg and then saved it as tif file). Now I want to upload it using the following code: System.Drawing.Image Bild = System.Drawing.Image.FromStream (PostedFile.PostedFile.InputStream); th...more >>

I need to convert the images to a 1bit (black and White) pcx (binary) file. I can read the image to a stream and write it a file. But I guess this is not it. Do I have to encode it to pcx or something like that? If so how do I do it? Please Advise. Thanks....more >>