T1CFreeImage is a simple ATL component that creates PNG images on the fly. T1CFreeImage is a simple ATL component that creates PNG images on the fly. It draws lines and texts with a selected color and saves the rendered image to a file. The component can be used with ASP, Word, Excel and any other applications that support ActiveX. It's supplied with full source code that you can easily extend with your own functions and use new versions of libraries as they become available. Platform: Windows 95/98/NT/2000. The more advanced and comprehensive ActiveX Image component can be found at http://www.tonec.com/download4.html. It fully supports Jpeg images (it doesn't support GIF since Unisys holds patent on LZW compression that is used in GIF format), direct stream data output, image reading/writing to a file and databases. It also works with different image sets, has many additional functions like text output with a selected slope, graphic primitives drawing, filled polygon, etc. If you want to build T1CFreeImage ActiveX component yourself, you will need to compile libraries (gd, libpng, zlib) first and then compile T1CfreeImage source files. To compile the libraries you need to create three subdirectories (gd, libpng, zlib) in your project home directory tree.
gd directory: It's necessary to download the source code of graphics library that creates images, draws graphic primitives and writes images to a file. The latest version can be downloaded from http://www.boutell.com/gd/. After the download you will need to unzip and move all source files (including some subdirectories) to gd directory. This library was developed by Thomas Boutell. We used 2.0 beta version for bulding binaries. Libpng directory. This library has a number of functions for working with PNG image files. The latest version can be downloaded from FreeSoftware web site: http://www.freesoftware.com/pub/png/libpng.html. We used version 1.09. zlib directory. Zlib library is used for PNG image compression. You can download it from http://www.freesoftware.com/pub/infozip/zlib/. We used version 1.1.3. T1CFreeImage directory. This is for T1CfreeImage ActiveX component itself. You can compile the libraries following the instructions included along with source code in their original distribution files. You can also take the project frame from T1CfreeImage distribution file, simply unzip and move libraries source code to created directories, and build the T1CFreeImage project. Since the projects have dependencies, all libraries should be compiled automatically and in the result you will get the ATL component in a single .dll file.
To build the component in MS VC 6.0 ++, you need to : Create T1CfreeImage project in ATL working directory (T1CFreeImage by default). Add ATL simple object and name it Images. (Menu Insert->New ATL object) In Project Settings, click on C/C++ tab and select Preprocessor Category in listbox, then add Additional include directories "../gd", "../libpng", "../zlib" Click on the "Link" tab, select "Input" category in the listbox and add Object/library modules: "libpng.lib" "zlib.lib" "gd.lib" to the end of the list. Also add "Additional library path": "../libpng/Release", "../zlib/Release", "../gd/Release" or other path depending on where these libraries are located. Add #include "gd.h" line in Images.h file right after #include "resource.h" line Add #include "gdfonts.h" in image.cpp right after #include "Images.h" line Add img member variable, set type to gdImagePtr. Access - public Add color variable. Add member variables with variables Type int. Access - public Add the following methods with the following code: Method Name: CreateImage Parameters: [in] int w, [in] int h Add the code: int white; img = gdImageCreate(w, h); white = gdImageColorAllocate(img, 255, 255, 255); Method Name: SetColor Parameters: [in] int R, [in] int G, [in] int B Add the code: color = gdImageColorAllocate(img, R, G, B); if (color == (-1)) { color = gdImageColorAllocate(img, R, G, B); color = gdImageColorClosest(img, R, G, B); } Method Name: DrawLine Parameters: [in] int x1, [in] int y1, [in] int x2, [in] int y2 Add the code: gdImageLine(img x1, y1, x2, y2, color); Method Name: DrawText Parameters: [in] int x, [in] int y, [in] BSTR str Add the code: CHAR *lpString; int iMessageSize; iMessageSize=wcslen(str)+1; lpString = new CHAR[iMessageSize]; // Change the Message From Unicode to MBCS if (WideCharToMultiByte(CP_ACP,0,str,-1,lpString,iMessageSize,NULL,NULL)==FALSE) { return(S_FALSE); } gdImageString(img, gdFontSmall, x, y, (unsigned char *)lpString, color); delete lpString; Method Name: SaveToFile Parameters: [in] BSTR strFile Add the code: FILE *out; CHAR *lpString; int iMessageSize; iMessageSize=wcslen(strFile)+1; lpString = new CHAR[iMessageSize]; // Change the Message From Unicode to MBCS if (WideCharToMultiByte(CP_ACP,0,strFile,-1,lpString,iMessageSize,NULL,NULL)==FALSE) { return(S_FALSE); } out = fopen(lpString, "wb"); /* Write PNG */ gdImagePng(img, out); fclose(out); delete lpString; Compile and build the project Register the component if needed. You will need it if you use DLL from our distribution file or if you use it on another computer.
> Here is the sample (t1c.vbs) that shows the usage of free ActiveX component on your ASP page. You can also use the component from VBS file, VBA for Access, Words and any other applications that support ActiveX (ATL) components. Dim im Set im = CreateObject("T1CFreeImage.Images.1") im.CreateImage 100,100 im.SetColor 255,0,0 im.DrawLine 10,10,30,30 im.SetColor 0,0,255 im.DrawText 10,40,"T1CFreeImage" im.SaveToFile "C:\test.png" Set im = Nothing
Figure 1. Test.png Download T1CFreeImage.zip with full source code and binary DLL (version 0.95). The more comprehensive and advanced version of component will become available in the middle of April, 2001. It will support Jpeg images and include text output with a slope, direct read/write to a stream, databases, ASP variable and file, more graphics primitives and error handling. The last release can be found at http://www.tonec.com/download4.html Note that Tonec Inc. also provides custom programming and cost-effective offshore software development services. Check out our Free Products page. If you have any questions, write to info@tonec.com