GPIMAGE 2
GpImage2 is a wrapper class that allows you to access all the main Gdi+ functions. Works great with all VFP versions, although it is not recommneded for VFP9 users, since we have available the GdiPlusX project, taht is a much complete project.
With GPIMAGE, drawing becomes super easy, and lots of other functionalities are available for VFP developers.
ROTATE TEXTS IN YOUR REPORTS FOR OLD VFP VERSIONS
Using Win32 (WinAPI) functions in Visual FoxPro
ProFox archives
COOL STUFF
Gradient Objects class
Gradient BackGrounds class
VFP Paint
GDI+ LINKS
GPIMAGE2 - access GDI+ with VFP6 and above
Download GDI+ Redistributable
GDI+ Flat API
Bob Powell's GDI+ FAQ
603 GDI+ DECLARE Craig Boyd
GDI+ Constants
GdiPlusX library
BLOGS
Andrew MacNeill
Bernard Bout
Bo Durban
Calvin Hsia
Carlos Alloatti
Colin Nicholls
Craig Boyd
Christof Wollenhaupt
Doug Hennig
Emerson Reed
Eric den Doop
Garret Fitzgerald
Herman Tan
Lisa Slater Nicholls
Rick Schummer
Rick Strahl
Sergey Berezniker
Please note that this is not a final version. The whole class is being improved and will be published soon with some new features in Universal Thread, where you can find the original version, without the drawing features, to dowload for free.
FOR CODE SAMPLES, VISIT THE FAQS PAGE !
GDI+ Image class is a VFP class to load, save and transform BMP, JPEG, GIF, PNG and TIFF images. It provides also conversion to/from Picture object, copying to/retrieving from clipboard, capturing of screen or any window.
New Methods included let you draw rectangles, lines, ellipsis, pies, strings and pictures on images. Brings the possibility to control alignment, size, orientation, rotation, of any shape, text or picture.
Description:
This class is based on GDI+ and requires gdiplus.dll which is freely available and can be installed on Win98 and higher. If you have not installed WinXP or .NET runtime then you can download this DLL from
http://www.microsoft.com/downloads/details.aspx?FamilyID=6a63ab9c-df12-4d41-933c-be590feaa05a&DisplayLang=en
or directly:
http://download.microsoft.com/download/platformsdk/redist/3097/W98NT42KMeXP/EN-US/gdiplus_dnld.exe
You can find some good information about GdiPlus on Microsoft official site:
And also great explanations and examples about GDI+ at
gpImage.prg file contains three classes. gpInit class declares required API functions and initializes GDI+. The single instance of this class must be created before use of gpImage or graphics classes and must exist all the time when GDI+ is used. Properties and methods of gpImage and Graphics classes are described below.
Properties:
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ImageFormat |
format of image: "BMP", "JPEG", "TIFF" etc. (read only) |
|
PixelFormat |
pixel format of image, for example "24bppRGB" (read/write) |
|
ImageWidth |
width of image (read only) |
|
ImageHeight |
height of image (read only) |
|
HorizontalResolution |
horizontal resolution in dpi (read/write) |
|
VerticalResolution |
vertical resolution in dpi (read/write) |
Methods:
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Create(tnWidth, tnHeight, tcPixelFormat) |
Creates an empty image object tcPixelFormat is optional; if omitted, default is 32bppARGB NEW |
|
Load(tcFileName) |
Loads an image from file |
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FromResource(tcFileName, tcBitmapName) |
Loads an image from bitmap resource in EXE/DLL file. Resource can be identified by name: img.FromResource("dxdiag.exe", "DIRECTX"), or by number: img.FromResource("shell32.dll", "#309"). |
|
FromPicture(toPicture) |
Creates an image object from Picture object |
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GetPicture() |
Returns Picture object |
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FromClipboard() |
Creates an image object from clipboard content |
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ToClipboard() |
Copies an image to clipboard |
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Thumbnail(tnWidth, tnHeight) |
Creates thumbnail of specified size |
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SaveAsBMP(tcFileName) |
Stores image in BMP file |
|
SaveAsJPEG(tcFileName, tnQuality, tnTransform) |
Stores image in JPEG file. Optional parameter tnQuality specifies quality of JPEG compression, 0 - highest compression, 100 - highest quality, default value - 75. Optional parameter tnTransform specifies type of transformation without loss of information, any of EncoderValueTransform values. |
|
SaveAsGIF(tcFileName) |
Stores image in GIF file |
|
SaveAsTIFF(tcFileName, tnCompress, tnColorDepth) |
Stores image in TIFF file. Parameter tnCompress specifies type of compression, any of EncoderValueCompression values, optional. Parameter tnColorDepth specifies number of colors in bits per pixel (1,4,8,16,24,32,48,64), optional. |
|
SaveAsPNG(tcFileName) |
Stores image in PNG file |
|
SaveAsMultipageTIFF(tcFileName, tnCompress, tnColorDepth) |
Stores image as first page of multipage TIFF file |
|
SaveAddPage(tnImage) |
Adds specified image as page of multipage file. Parameter tnImage is a value, returned by GetImage() function of another image object. |
|
GetImage() |
Returns pointer to GDI+ image object which can be used in API functions and SaveAddPage() function. |
|
GetPixelColor(x, y) |
Returns color value of pixel |
|
GetPixelAlpha(x, y) |
Returns alpha value of pixel |
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SetPixel(x, y, tnColor, tnAlpha) |
Sets color and alpha values of pixel |
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Crop(x, y, tnWidth, tnHeight) |
Crops an image |
|
RotateFlip(rotateFlipType) |
Rotates and flips an image |
|
Resize(tnWidth, tnHeight, tnInterpolationMode) |
Resizes an image |
|
GetPageCount() |
Returns number of pages in multipage (TIFF) file |
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SelectPage(tnPage) |
Selects the specified page |
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GetFrameCount() |
Returns number of time frames in multiframe (GIF) file |
|
SelectFrame(tnFrame) |
Selects the specified time frame |
|
Capture(thWnd) |
Captures the window, specified by handle or desktop, if handle is not specified |
Now we introduced a new class that is responsible for drawing on the image selected / created - Graphics, that contains some new functions. Take care that to use this functions, you MUST first call GpInit and GpImage.
gdip = CreateObject("gpInit")
img = CreateObject("gpImage")
oGr = CreateObject("Graphics",img.getimage()) && to work with Image Context
or
oGr = CreateObject(“Graphics”,Thisform.Hwnd,”HWND”) && to work directly on the desired form NEW
see example file TESTDRAW.PRG
Properties:
|
StringMeasure |
Determines if measurement of string is always needed; StringW, StringH, StringChars and StringLines will always be updated after drawing any string. DEFAULT = .T. |
|
StringW |
String Width of last string (read only) |
|
StringH |
String Height of last string (read only) |
|
StringChars |
String Characters fitted in string (read only) |
|
StringLines |
String Lines filled in string (read only) |
|
SmoothingMode |
Specifies rendering quality, with possible values indicated by GDIPLUS_SmoothingMode_* constants |
|
InterpolationMode |
Specifies the interpolation mode associated with this graphics object |
Methods:
|
CreateFromImage(tnImageHandle) |
Creates Graphics from Image Handle NEW |
|
CreateFromHWND(tnFormHWND) |
Creates Graphics from Form’s HWND NEW |
|
SetPen(tnColor, tnWidth, tnUnit) |
Sets the pen to be used by “DrawRect”, “DrawLine”; tnWidth (1) and tnUnit (0)are optional NEW More great information about PEN at http://www.bobpowell.net/pensone.htm |
|
DrawLine(x1, y1, x2, y2) |
Draws a Line between two points x1y1 and x2y2, based on “SetPen” |
|
DrawRect(x, y, tnWidth, tnHeight) |
Draws a rectangle based on “SetPen” |
|
DrawEllipse(x, y, tnWidth, tnHeight) |
Draws an ellipse based on “SetPen” |
|
DrawPie(x, y, tnWidth, tnHeight, nStart, nSweep)
|
Draws a pie slice based on “SetPen” nStart = starting point to start draw nSweep = Size in angles of the slice (0-360) NEW |
|
DrawArc(x, y, tnWidth, tnHeight, nStart, nSweep) |
Draws an arc, using same parameters of “DrawPie”; Portion of circle within the rectangle defined by the angles NEW |
|
DrawPolygon(taPoints) |
Draws a polygon based on “SetBrush” taPoins = 2-D array with integer positions column1 = X ; column 2 = Y also connects first and last points to close the figure drawn. NEW |
|
SetBrush(tnColor, tnAlpha) |
Sets the Brush to be used by “FillRect” and “DrawString” Sets color and alpha values of pixel Alpha ranges from 0 (transparent) to 255 (opaque) NEW More great information on BRUSHES at http://www.bobpowell.net/brushesone.htm |
|
SetHatchBrush(tnHatchStyle, tnBackCol, tnBackAlpha, tnForeCol, tnForeAlpha) |
Creates a HatchBrush object based on a hatch style, a foreground color, and a background color tnHatchStyle is numeric constant. See codes in Gpimage.h NEW |
|
SetTextureBrush(tcFileName, tnWrapMode) |
Creates a TextureBrush object based on an image and a wrap mode. The size of the brush defaults to the size of the image, so the entire image is used by the brush. tnWrapMode is numeric constant. See codes in Gpimage.h NEW |
|
SetGradientBrush(tnX, tnY, tnWidth, tnHeight, tnColor1, tnColor2, tnGradientMode) |
Creates a LinearGradientBrush object based on a rectangle, two colors, and a gradient mode. NEW |
|
FillRect(x, y, tnWidth, tnHeight) |
Draws and Fills a rectangle based on “SetBrush” |
|
FillEllipse(x, y, tnWidth, tnHeight) |
Draws and Fills an ellipse based on “SetBrush” |
|
FillPie(x, y, tnWidth, tnHeight, nStart, nSweep) |
Draws and Fills a pie slice based on “SetPen” nStart = starting point to start draw nSweep = Size in angles of the slice (0-360) NEW |
|
FillPolygon(taPoints) |
Draws and Fills a polygon based on “SetBrush” taPoins = 2-D array with integer positions column1 = X ; column 2 = Y NEW |
|
SetRect(x, y, tnWidth, tnHeight) |
Sets a rectangle in which “DrawString” will draw the text |
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TranslateTransform(tnX, tnY) |
Translates by (x,y) the graphics object NEW |
|
RotateTransform(tnAngle) |
Sets the rotaion by the specified angle, based on the matrix created by “TranslateTransform” NEW |
|
ResetTransform |
Resets the transform matrix NEW |
|
SetAlignment(thAlignment, tvAlignment, tFlags) |
Sets the horizontal, vertical and flags for the “DrawString” alignment. The three parameters are numeric constants. See codes in Gpimage.h NEW |
|
DrawString(tcText, tcFontName, tnFontSize, tcFontStyle, tlMeasureString) |
Draws a String on the image, based to “SetBrush”, “SetAlignment” and “SetRect”. tcFontStyle is character “B” – Bold “I” – Italic “U” – Undeline “S” – Superscript tlMeasureString is optional; .T. sends string measures to properties StringW, StringH, StringChars and StringLines NEW More great information on DRAWING STRINGS at http://www.bobpowell.net/begintext.htm |
|
MeasureString(tcText, tcFontName, tnFontSize, tcFontStyle) |
Same parameters as “DrawString” – updates properties StringW, StringH, StringChars and StringLines NEW |
|
DrawImage(tcImageFile, x, y, tnWidth, tnHeight) |
Draws a picture on the image tcImageFile can be either the file name or handle of another loaded image in another instance of gpimage (see examples) NEW tnWidth and tnHeight are optional More great information on DRAWING IMAGES at http://www.bobpowell.net/imagesone.htm |
|
DrawImageScaled(tcImageFile, x, y, tnWidth, tnHeight) |
Draws a picture on the image Scaled to the size of the virtual rectangle |
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DrawImageRectRect(tcFileName, dstx, dsty, dstwidth, dstheight, srcx, srcy, srcwidth, srcheight) |
Draws the specified portion of the specified Image object at the specified location and with the specified Size. This method will draw the image using the IMAGEATTRIBUTES predefined in REMAPTABLE and SETCOLORMATRIX (see below) NEW |
|
RemapTable(tnOldColor, tnNewColor, tnOldAlpha, tnNewAlpha) |
Converts the colors in an image according to a color remap table. Makes possible to change some desired colors. This command creates an ImageAttributes. To apply the changes, draw the Remapped Image using DRAWIMAGERECTRECT NEW See example file REMAPPINGCOLORS.PRG |
|
SetColorMatrix(taColMatrix) |
The ColorMatrix structure contains a 5x5 matrix of real numbers. Using this matrix it is possible to make adjustments in image colors. See example file MATRIX.PRG Check also in MSDN article “Using a Color Matrix to Transform a Single Color” NEW More great information about COLOR MATRICES at http://www.bobpowell.net/negativeimage.htm |
|
ChangeColors(tnRed, tnGreen, tnBlue, tnAlpha) |
This is the easiest way to convert colors. tnRed, tnGreen, thBlue and tnAlpha represent the percentage of a single color you need to add / decrease in the image. Ranges from -100 to +100 All 4 parameter are needed
It has also 2 predefined color matrices To use them, sen only one parameter 1 for Black and White convesion 2 for negative conversion
Soon I will be adding some new matrices that deal with brightness and contrast. NEW
To better understand this method you should run example file TESTGPIMAGE.SCX and CHANGECOLORS.PRG |
|
GetGraphics |
Gets the graphics handle |
Now you can also work with IMAGEATTRIBUTES, changing or creating new ColorMatrix’es, RemappingTables of colors. With this feature, you can transform any image to Bçack and White, negative, adjust brightness / contrast, increase or decrease Red, Green, Blue or Alpha Color Attributes very easily. With no more than 5 lines of code you can produce the effects below:
