[ABU] 12-Aug-2020 Blend2d 1.0 Beta 1 has been released TclTk binding for Blend2d has been released. https://sourceforge.net/projects/irrational-numbers/files/tclBlend2d/blend2d-1.01.zip/download%|%Download blend2d-1.0b1%|% The package contains prebuilt binaries for Win-x64, Linux-x64 and MacOS. Within the package you can find a reference manual and a lot of demos. * ''Please note that Tcl-Blend2d for MacOS has several limitations. You can use it for generating images, but trying to use it with 'live images' is extremely slow, and moreover there's still the problem of red/blue channell swapping (Funny!). I think this is due with the (poor) MacOS Xlib-emulation, but I couldn't solve it, yet!. Any help is appreciated.'' https://drive.google.com/file/d/1uWmwInHN6VFWGiwSoao-Tt3zYmIyjEdg/view?usp=sharing%|%Video%|% [Blend2d-Tiger] <> INTRODUCTION '''TclBlend2d '''is a Tcl package for working with the https://blend2d.com%|%Blend2d%|% graphics engine. <
> '''Blend2d''' is an open source, high quality, high performance vector graphics engine '''TclBlend2d '''is a multiplatform binary package including Blend2d library for Windows and Linux; MacOS support is planned. Images created with '''TclBlend2d ''' can be saved as BMP files, or exchanged with the tk-photo images. TclBlend2s provides also a new type of tk-image (named "'''blend2d'''") you can embed in your widgets much like a tk-photo image. <
> You can draw on a "blend2d" tk-image and istantly see the changes in the widgets that have this image attached. TclBlend2d closely matches the Blend2d C++ API with the exception of cases where more Tcl-ish way is more appropriate. **DEFINITIONS and CONCEPTS** ***SURFACES*** The main concept of TclBlend2d is the '''Surface'''. A '''Surface''' comes with an internal pixmap (32bit depth, with alpha support) and holds all of the graphics state parameters that describe how drawing is to be done. This includes parameters like the current line width, the current color (or gradient), a 2D transformation matrix and many other things. <
>It allows the actual drawing function to take fewer arguments to simplify the interface. A Surface implements an immediate-mode rendering; there's no concept of 'scene' or display-list like in the tk-canvas widget; if you want to delete or move a part of the pixmap, you should erase everything and restart drawing from the beginning. The whole graphic-state can be saved on an internal Surface's stack. Any subsequent changes to the graphics state can then be undone quickly by simply restoring the previous graphics-state. TclBlend2d provides support for simple and complex geometrical entities. <
> Among the simple geometrical entities, you can find lines, arcs, (rounded) rectangles and many others. <
> A '''Path '''is a complex geometrical entity made of lines and curves (quadratics and cubics Bezier's curves). A Surface provides just two methods for drawing the geometrical entities: '''fill''' and '''stroke'''. A geometrical entity can be stroked or filled with a '''style''', i.e a solid colr, a gradient or a pattern. ***COLORS, STYLES and COMPOSITION-OPS*** When you stroke/fill a geometrical entity, you are not limited to use an uniform color; when you do a stroke/fill, you apply a '''style'''. A '''style '''can be * an uniform color (with alpha transparency) * a gradient * a pattern (i.e. a bitmap) Styles may have their own alpha-transparency, and when you do a fill/stroke, pixels are blended with the pixels already stored in the internal pixmap. You can set a '''composition op''' for controlling how the new colors are blended with the destination. ***MORE on STROKING*** TclBlend2d provides support for controlling how a (complex) stroke is rendered: caps, joins, miter, dashes, ... ***COORDINATE SYSTEMS and TRANSFORMATIONS*** By default the coordinates you specify (''user-coords'') coincide with the coords of the internal pixmap (''pixmap-coords''), being (0.0 0.0) the top-left corner. <
> You can set and combine a transformation matrix (translation, rotation,scale,...),then all your following coordinates you specify with the fill/stroke methods are accordingly multiplied. <
> These transformations are part of the whole Surface's graphics-state and then they can be pushed on the Surface's stack. ***TEXT*** TclBlend2d provides support for simple text layout. It can also parse and extract glyphs from most common font-files. <
> Glyphs can also be transformed in '''Path''' (i.e. set of curves) and then analitically manipulated in terms of contours and single curves. ***IMAGES*** TClBlend2d has builtin support for reading BMP, PNG and JPG files. <
> Currently support for writing is limited to BMP, but you can save the generated image in a tk-photo and then save it in any other format ... Note that you can import/save just a part of an image (a tk-photo or another Surface), and when you import an image in a Surface, the image is transformed based on the current transformation matrix, i.e. it is properly scaled/rotated. ---- ''This concludes this short introduction to the basic features and concepts for working with TclBlend2d.'' <
> ''For further details, read the Getting-started section, look at the demos included with the package, an read the reference manual...'' <> <> Getting Started '''How to create and view an image generated with blend2d ?''' Let's create a very simple image with Blend2d ====== package require Blend2d BL::Surface create mySfc mySfc clear mySfc fill [BL::circle {200 200} 50] -style [BL::color orange] ... you got the idea ... ====== then we could: * save it in a file (currently only .BMP is supported) ====== mySfc save "./image01.bmp" ====== * copy the image in a tk-photo ====== image create photo photo1 mySfc writeToTkphoto photo1 ====== ... and then embed photo1 in a widget, or save it in a file ... But we could also create a totally new kind of image that can be embedded in a widget and manipulated in real time... You already know how to display a tk-photo in a widget like a canvas or a label. tclBlend2d provides a new type of image named "blend2d". ====== image create blend2d mySrf1 ====== "mySrf1" is both a new image, and a BL::Surface object (i.e. a command). So, you can embed this image in a widget ====== label .a -image mySrf1 pack .a ====== and then draw on "mySrf1" ... ====== mySrf1 clean mySrf1 fill [BL::circle {100 100} 80] -style [BL::color red] ...` ====== You can continue to draw in mySrf1, and istantly see the results in the label-widget. <> <> Reference Manual -Blend2d 1.0 beta1 '''tclBlend2d 1.0b1''' ''Tcl meets Blend2d'' Tcl meets Blend2d **SYNOPSIS** package require '''Tcl 8.6''' package require '''Blend2d ?1.0b1?''' * '''BL::Surface''' '''create''' ''sfcName'' ?options? * '''BL::Surface''' '''new''' ?options? * ''sfcName'' '''destroy''' * '''BL::Surface''' '''names''' * ''sfcName'' '''configure''' * ''sfcName'' '''cget''' ''optionName'' * ''sfcName'' '''configure''' ''optionName'' * ''sfcName'' '''configure''' ''optionName'' ''optionValue'' ?''optionName'' ''optionValue'' ...? * ''sfcName'' '''push''' * ''sfcName'' '''pop''' * ''sfcName'' '''stacksize''' * ''sfcName'' '''reset''' * '''BL::rgb''' ''RR'' ''GG'' ''BB'' ?''alpha''? * '''BL::color''' ''colorName'' ?''alpha''? * '''HSB''' ''hue'' ''sat'' ''brightness'' ?alpha? * '''BL::gradient''' ''type'' ''values'' ''stopList'' ?options? * '''BL::pattern''' ''sfcName''|''filename'' ?options? * '''BL::line''' ''{x0 y0}'' ''{x1 y1}'' * '''BL::polyline''' ''{x0 y0}'' ''{x1 y1}'' ?''{x2 y2}'' ....? * '''BL::polygon''' ''{x0 y0}'' ''{x1 y1}'' ?''{x2 y2}'' ....? * '''BL::box''' ''{x0 y0}'' ''{x1 y1}'' * '''BL::rect''' ''x'' ''y'' ''w'' ''h'' * '''BL::roundrect''' ''x'' ''y'' ''w'' ''h'' ''rx'' ?''ry''? * '''BL::circle''' ''{cx cy}'' ''r'' * '''BL::ellipse''' ''{cx cy}'' ''rx'' ''ry'' * '''BL::arc''' ''{cx cy}'' ''rx'' ''ry'' ''start'' ''sweep'' * '''BL::pie''' ''{cx cy}'' ''rx'' ''ry'' ''start'' ''sweep'' * '''BL::chord''' ''{cx cy}'' ''rx'' ''ry'' ''start'' ''sweep'' * '''BL::text''' ''{x y}'' ''font'' ''text'' * ''sfcName'' '''stroke''' ''geometry'' ?options? * ''sfcName'' '''fill''' '''all'''|''geometry'' ?options? * ''sfcName'' '''clear''' ?options? * ''sfcName'' '''flush''' * ''sfcName'' '''size''' * ''sfcName'' '''userToMeta''' * '''BL::path''' '''create''' ''pathName'' * '''BL::path''' '''new''' * ''pathName'' '''destroy''' * '''BL::Path''' '''names''' * ''pathName'' '''dup''' * ''pathName'' '''add''' ''geometry'' ?''geometry'' ...? ?''options''? * ''pathName'' '''apply''' ''matrix'' * ''pathName'' '''fitTo''' ''x'' ''y'' ''w'' ''h'' * ''pathName'' '''moveTo''' ''point0'' * ''pathName'' '''lineTo''' ''point'' * ''pathName'' '''quadTo''' ''point1'' ''point2'' * ''pathName'' '''cubicTo''' ''point1'' ''point2'' ''point3'' * ''pathName'' '''smoothQuadTo''' ''point2'' * ''pathName'' '''smoothCubicTo''' ''point2'' ''point3'' * ''pathName'' '''arcQuadrantTo''' ''point1'' ''point2'' * ''pathName'' '''arcTo''' ''pointC'' ''pointR'' ''start'' ''sweep'' ?'''-moveto''' ''boolean''? * ''pathName'' '''ellipticArcTo''' ''point1'' ''pointR'' ''rotation'' ''largeArcFlag'' ''sweepFlag'' ''point1'' * ''pathName'' '''close''' * ''pathName'' '''reset''' * ''pathName'' '''shrink''' * ''pathName'' '''bbox''' * ''pathName'' '''view''' * ''pathName'' '''contour''' * ''pathName'' '''contour''' ''i''|'''*''' * ''pathName'' '''contour''' ''i''|'''*''' ''j''|'''*''' ''OP'' ''t'' * '''BL::FontFace''' '''create''' ''faceName'' ''fontfile'' ?''faceIdx''? * '''BL::FontFace''' '''new''' ''fontfile'' ?''faceIdx''? * ''faceName'' '''destroy''' * '''BL::FontFace''' '''names''' * ''faceName'' '''details''' * '''BL::Font''' '''create''' ''fontName'' ''faceName'' ''fontsize'' * '''BL::Font''' '''new''' ''faceName'' ''fontsize'' * ''fontName'' '''destroy''' * '''BL::Font''' '''names''' * ''fontName'' '''glyphs''' ''someText'' * ''fontName'' '''glyph''' ''glyphIdx'' * ''sfcName'' '''load''' ''filename'' * ''sfcName'' '''save''' ''filename'' ?'''-format''' ''file-format''? * ''sfcName'' '''copy''' ''srcSurface'' ?'''-from''' ''{x0 y0 w h}''? ?'''-to''' ''{xp yp}''? ?'''-compop''' ''op''? ?'''-globalalpha''' ''alpha''? * ''sfcName'' '''copy''' ''srcSurface'' ?'''-from''' ''{x0 y0 w h}''? ?'''-to''' ''{x y w h}''? ?'''-compop''' ''op''? ?'''-globalalpha''' ''alpha''? * ''sfcName'' '''readFromTkphoto''' ''tkphoto'' ?'''-from''' ''{x0 y0 w h}''? ?'''-to''' ''{x0 y0 w h}''? * ''sfcName'' '''writeToTkphoto''' ''tkphoto'' ?'''-from''' ''{x0 y0 w h}''? ?'''-to''' ''{x0 y0 w h}''? * '''image''' '''create''' '''blend2d''' ?''name''? ?''options''? * '''BL::classes''' * '''BL::classinfo''' ''objectName'' * '''BL::codecs''' * '''BL::enum''' * '''BL::enum''' ''category'' * '''BL::libinfo''' * '''BL::platform''' * '''Mtx::identity''' * '''Mtx::MxM''' ''M1'' ''M2'' * '''Mtx::determinant''' ''M'' * '''Mtx::invert''' ''M'' * '''Mtx::PxM''' ''P'' ''M'' * '''Mtx::multiPxM''' ''Points'' ''M'' * '''Mtx::P-P''' ''P1'' ''P2'' * '''Mtx::VxM''' ''V'' ''M'' * '''Mtx::translation''' ''dx'' ''dy'' * '''Mtx::scale''' ''sx'' ?''sx''? ?''C''? * '''Mtx::rotation''' ''angle'' '''radians'''|'''degrees''' ?''C''? * '''Mtx::skew''' ''sx'' ''sy'' * '''Mtx::xreflection''' * '''Mtx::yreflection''' * '''Mtx::translate''' ''M'' ''dx'' ''dy'' * '''Mtx::post_translate''' ''M'' ''dx'' ''dy'' * '''Mtx::scaling''' ''M'' ''sx'' ''sy'' ?''C''? * '''Mtx::post_scaling''' ''M'' ''sx'' ''sy'' ?''C''? * '''Mtx::rotate''' ''M'' ''angle'' '''radians'''|'''degrees''' ?''C''? * '''Mtx::post_rotate''' ''M'' ''angle'' '''radians'''|'''degrees''' ?''C''? * '''Mtx::yreflect''' ''M'' * '''HSB''' ''h'' ''s'' ''b'' ?''alpha''? * '''RGB2HSB''' ''0xAARRGGBB'' **DESCRIPTION** Package '''Blend2d''' integrates the https://blend2d.com%|%Blend2d%|% vector engine in Tcl/Tk. http://blend2d.com%|%Blend2d%|% is an open source, high quality, high performance vector graphics engine. '''Blend2d''' is a binary package, distributed in a multi-platform bundle, i.e. it can be used on * Windows 64 bit * Linux 64 bit * MacOS 64 bit (... some limitations ...) Just an example to get the flavor of how to use '''Blend2d''': ====== # draw a circle ... package require Blend2d set sfc [BL::Surface new] $sfc clear $sfc configure -fill.style [BL::color orange] $sfc fill [BL::circle {150 150} 100] $sfc save "./image01.bmp" $sfc destroy ====== **Blend2d with and without Tk** You can run '''Blend2d''' from a tclsh interpreter, without loading '''Tk'''. The following command ====== package require tclBlend2d ====== can be used in a '''tclsh''' interpreter to load the package without requiring '''Tk''' support. You will be still able to generate and save images, but of course some subcommands related to Tk won't be available. The command ====== package require tkBlend2d ====== loads the full package (and requires '''Tk'''). Note that ====== package require Blend2d ====== is equivalent to ====== package require tkBlend2d ====== **BL::Surface and the graphics state parameters** The main concept of Tcl-Blend2d is the '''Surface'''. A '''Surface''' comes with an internal framebuffer (32bit depth, with alpha support) and holds all of the graphics state parameters that describe how drawing is to be done. This includes parameters like the current line width, the current color (or gradient), a 2D transformation matrix and many other things. A '''Surface''' can be created with the following commands '''BL::Surface''' '''create''' ''sfcName'' ?options?: creates a new instance of the class '''BL::Surface''' called ''sfcName''. Options can be set at creation time, or later with the '''configure''' method. '''BL::Surface''' '''new''' ?options?: creates a new instance of the class '''BL::Surface''' returning a new unique ''sfcName''. Options can be set at creation time, or later with the '''configure''' method. ''sfcName'' '''destroy''': destroys ''sfcName''. Note that in general any oo-object like ''sfcName'' should be explicitly destroyed '''BL::Surface''' '''names''': returns the list of all the currently allocated surfaces. The whole set of Surface's options is also called the drawing state. A drawing state consists of * the 2D transformations that have been applied (i.e. translate, rotate and scale ... see below), * the current values of various attributes controlling how to fill and how to stroke all the basic and complex ''geometric entities'', and it can be manipulated with the '''cget'''/'''configure''' methods. ''sfcName'' '''configure''': returns a list with all the valid options and their values. ''sfcName'' '''cget''' ''optionName'': returns the current value of the option ''optionName''. Raise an error if ''optionName'' is not a valid option. ''sfcName'' '''configure''' ''optionName'': returns a list with two values: the named option and its value. Raise an error if ''optionName'' is not a valid option. ''sfcName'' '''configure''' ''optionName'' ''optionValue'' ?''optionName'' ''optionValue'' ...?: modifies all the named options with the specified values. Raise an error if any ''optionName'' is not recognized or its ''optionValue'' is not valid; in this case no option is modified. Surface options are: '''-threads''' ''count'': If ''count'' is >=1 then all the rendering commands are queued and executed by worker-threads when needed (i.e. before exporting an image or,if the surface is a Tkimage, in the event-loop) Default is 0 (i.e all the rendering commands are run immediately (synchronous mode)). '''-format''' ''{dx dy {?'''PRGB32''' | '''XRGB32'''?}}'': sets the size (in pixel) and type of the internal framebuffer. ''WARNING'': When user sets a new '''-format''', the previous content of the framebuffer is lost, and the new framebuffer is unitialized (it contains garbage). It is user's responsability to clean it or to properly restore the previous contents. Default is '''{400 400 PRGB32}''' '''-matrix''' ''matrix'': ''matrix'' defines the affine transformations that will be applied to the next geometric entities specified with the "fill" or "stroke" operations See the section "Affine Matrix" for more details. Default is '''{1.0 0.0 0.0 1.0 0.0 0.0}''' (Identity matrix) '''-metamatrix''' ''matrix'': This is a readonly option. metamatrix is (TO BE DOC'ed...) '''-compop''' ''compositionOp'': defines how colors should be blended. For further details try googling "Porter-Duff composition" or "Alpha composition". Default is '''SRC_OVER'''. '''-globalalpha''' ''alphaValue'': defines a global alpha value. ''alphaValue'' should be between '''0.0''' (transparent) and '''1.0''' (opaque). Default value is '''1.0''' '''-fill.style''' ''style'': defines the style to be used for filling. ''style'' can be a solid-color (with alpha transparency), a gradient,or a pattern ... Default is '''0xFF000000''' (Opaque Black). See the "Setting a style" section below. '''-fill.alpha''' ''alphaValue'': defines the alpha value for '''fill''' operations. ''alphaValue'' should be between '''0.0''' (transparent) and '''1.0''' (opaque). Default value is '''1.0''' '''-fill.rule''' ''mode'': defines how to fill intersecting curves. Default is '''NON_ZERO''' '''-stroke.style''' ''style'': defines the style to be used for stroking. ''style'' can be a solid-color (with alpha transparency), a gradient,or a pattern. Default is '''0xFF000000''' (Opaque Black) See above notes for '''-fill.style''' '''-stroke.alpha''' ''alphaValue'': desfines the alpha value for '''stroke''' operations. ''alphaValue'' should be between '''0.0''' (trasnparent) and '''1.0''' (opaque). Default value is '''1.0''' '''-stroke.width''' ''width'': defines the width of the strokes (outlines). Default value is '''1.0'''. Note that the stroke width is scaled accordling to the current matrix transformation. If you want a constant width, independent of the current scale factor, you should use the '''-stroke.transformorder''' option. '''-stroke.dashoffset''' ''offset'': defines the offset on the rendering of the associated dash array. Default is '''0.0''' '''stroke.join''' ''mode'': defines how the junction point of two consecutive segment will be stroked. Default is '''MITER_CLIP''' '''-stroke.miterlimit''' ''value'': defines the limit on the ratio of the miter length to the stroke-width used to draw a miter join. When the limit is exceeded, the join is converted from a miter to a bevel. Default is '''4.0'''. '''-stroke.cap''' ''capMode'': '''-stroke.cap''' {''startCap endCap''}: ''capMode'' specifies how to render the extremities of the stroke. ''capMode'' may be a list of two values to specify the ''startCap'' and the ''endCap'' separately. Default is '''{BUTT BUTT}''' '''-stroke.transformorder''' ''mode'': Default is '''AFTER'''. The whole drawing-state can be stored on an ''internal stack'', and you can inspect, save and restore the whole drawing state (i.e. all the options) with just the following commands: ''sfcName'' '''push''': saves the current graphic-state on an internal stack. ''sfcName'' '''pop''': pops the graphic-state from the stack. Raise an error if stack is empty. ''sfcName'' '''stacksize''': returns the size of the internal stack (i.e. number of saved graphic-states) ''sfcName'' '''reset''': eesets the whole surface's graphic-state, including the internal stack. All the options (but '''-format''' and '''-threads''') are reset to their default values. ***Setting a style*** There are 3 types of styles you can set for strokes and fills: SOLID, GRADIENT, PATTERN * A '''SOLID''' style is an uniform color (with optional alpha transparency). It can be specified as a simple hex number in 0xAARRGGBB format, 0xFFFF0000 is red 0xFF0000FF is blue or through the following utilities: '''BL::rgb''' ''RR'' ''GG'' ''BB'' ?''alpha''?: returns a 0xAARRGGBB color by combining the ''RR'' ''GG'' ''BB'' and the (optional) ''alpha'' arguments. ''RR'', ''GG'', ''BB'' are integers 0..255 (best expressed as 0x00..0xFF), ''alpha'' is an optional parameter ranging from 0.0 (transparent) to 1.0 (opaque). Default ''alpha'' is 1.0 '''BL::color''' ''colorName'' ?''alpha''?: returns a 0xAARRGGBB color by combining the ''colorName'' and the (optional) ''alpha'' arguments. ''colorName'' is a color name (e.g "lightblue") or a numeric-color like #rrggbb, ''alpha'' is an optional parameter ranging from 0.0 (transparent) to 1.0 (opaque). Default ''alpha'' is 1.0 '''HSB''' ''hue'' ''sat'' ''brightness'' ?alpha?: This is an alternative way for specifying a color (HSB model). See the "HSB color model" section at the end for more details. * A '''GRADIENT''' can be specified with the following syntax: '''BL::gradient''' ''type'' ''values'' ''stopList'' ?options?: * ''type'' should be one of the following values: LINEAR, RADIAL, CONICAL * ''values'' is a list of parameters (depending on ''type'') * BL::gradient LINEAR {x0 y0 x1 y1} _stopList_ ?_options_? * BL::gradient RADIAL {x0 y0 x1 y1 radius} _stopList_ ?_options_? * BL::gradient CONICAL {x0 y0 angle} _stopList_ ?_options_? * ''stopList'' is a list of offset and colors (at least two pairs of offset color) * ''offset'' is a number between 0.0 and 1.0 * ''color'' can be expressed as an hex number (0xAARRGGBB) or with the above cited '''BL::rgb''' , '''BL::color''', '''HSB''' commands. * ''options'' are: '''-mode''' ''extendMode'': defines how to extend or repeat the style outside the defined region. Default is '''PAD'''. See command "'''BL::enum''' '''EXTEND_MODE'''" for valid values. '''-matrix''' ''mtx'': defines an auxiliary 2D tranformation that should be combined with the current transformation matrix. Gradient example: ====== # define an oblique LINEAR gradient set gr1 [BL::gradient LINEAR {0 0 400 400} \ [list 0.0 [BL::color lightblue] 0.8 [BL::color blue] 1.0 [BL::rgb 0 0 0 0.1]] \ ] $sfc fill [BL::circle {200 200} 100] -style $gr1 ====== * A '''PATTERN''' can be specified with the following syntax: '''BL::pattern''' ''sfcName''|''filename'' ?options?: defines a pattern based on another ''sourceBitmap'', i.e a ''SfcName'', or an external JPEG,PNG,BMP ''filename''. Valid '''options''' are: '''-mode''' ''extendMode'': same as for '''BL::gradient''' '''-matrix''' ''mtx'': same as for '''BL::gradient''' '''-from''' ''{x y w h}'': defines the pattern based on a rectangular subregion of the ''srcBitmap''. ''x'', ''y'', ''w'',''h'' are pixel coords (integer coords) ***Geometric types*** Blend2D provides both simple geometric types ( line, rectangle, circle ....) and complex geometric types (Path, Region). The main difference between simple and complex geometry types derives from their implementation. Although all the geometric types could be implemented as oo-classes, this will tend to develop programs difficult to maintain, since in Tcl oo-objects should be explicitly destroyed. Therefore most of the following commands for building geometric types don't return oo-objects but simple tcl-lists/dictionaries, that are automatically disposed when they go out of scope. Just two complex geometry-types ('''BL::Path''' and '''BL::Region''') are implemented as oo-classes, (and then it's programeeers's responsability to explicitly destroy 'em). A simple example for drawing a simple geometry is ====== $sfcName fill [BL::box 0 0 120 175.8] ====== The supported simple-geometries are: '''BL::line''' ''{x0 y0}'' ''{x1 y1}'': '''BL::polyline''' ''{x0 y0}'' ''{x1 y1}'' ?''{x2 y2}'' ....?: '''BL::polygon''' ''{x0 y0}'' ''{x1 y1}'' ?''{x2 y2}'' ....?: '''BL::box''' ''{x0 y0}'' ''{x1 y1}'': '''BL::rect''' ''x'' ''y'' ''w'' ''h'': '''BL::roundrect''' ''x'' ''y'' ''w'' ''h'' ''rx'' ?''ry''?: '''BL::circle''' ''{cx cy}'' ''r'': '''BL::ellipse''' ''{cx cy}'' ''rx'' ''ry'': '''BL::arc''' ''{cx cy}'' ''rx'' ''ry'' ''start'' ''sweep'': '''BL::pie''' ''{cx cy}'' ''rx'' ''ry'' ''start'' ''sweep'': '''BL::chord''' ''{cx cy}'' ''rx'' ''ry'' ''start'' ''sweep'': '''BL::text''' ''{x y}'' ''font'' ''text'': Note that all these commands defining ''simple geometry types'' start with a lowercase letter. These commands do not create oo-objects; they simply return a special crafted list that should be passed to the '''fill'''/'''stroke''' methods. These objects (lists/dictionaries!) don't require an explicit "destroy" method. Other than ''simple geometries'' there are ''complex geometries'' like '''BL::Path''' and '''BL::Region''' and they will be described in the following sections. ***Drawing on a surface*** ''sfcName'' '''stroke''' ''geometry'' ?options?: draws the outline of the specified ''geometry'', accordling to the current drawing-state. Extra options listed after ''geometry'' are temporary set just for this operation. Note that some options like '''-stroke.width''', '''-stroke.style''', can be abbreviated as '''-width''', '''-style''', and so on. ''sfcName'' '''fill''' '''all'''|''geometry'' ?options?: draws (fills) the specified ''geometry'', accordling to the current drawing-state. The special geometry '''all''' means "the whole framebuffer". Extra options listed after ''geometry'' are temporary set just for this operation. Note that within this fill operation, the option '''-fill.style''' can be abbreviated as '''-fill'''. ''sfcName'' '''clear''' ?options?: This is a shorthand for "''sfcName'' '''fill''' '''all''' ?options?" ***Other Surface commands*** ''sfcName'' '''flush''': flushes the internal rendering command queue and wait for its completion (will block). (only useful in Multi-Thread contexts). This command is normally unnecessary, since a flush() is automatically performed before the image is copied/exported/displayed. ''sfcName'' '''size''': returns a list of two values: width and height of the surface (in pixel) ''sfcName'' '''userToMeta''': sets the surface MetaMatrix. TO BE DOC'ed ... **BL::Path** The following commands can be used for creating and manipulating a '''Path''': '''BL::path''' '''create''' ''pathName'': creates a new instance of the class '''BL::Path''' called ''pathName''. '''BL::path''' '''new''': creates a new instance of the class '''BL::Path''' returning a new unique ''pathName''. ''pathName'' '''destroy''': destroys ''pathName''. '''BL::Path''' '''names''': returns the list of the currently available paths ''pathName'' '''dup''': duplicates ''pathName''. Return a new path ''pathName'' '''add''' ''geometry'' ?''geometry'' ...? ?''options''?: adds one or more ''geometry'' to ''pathName''. ''geometry'' is any geometric type above defined, including the same ''pathName''. Valid options are: '''-direction''' ''value'': ''value'' can be one of '''NONE''', '''CW''', '''CCW'''. Default is '''CW'''. Hint: Use '''CCW''' for adding holes in a path '''-matrix''' ''matrix'': applies a 2D transformation to the added geometries. ''pathName'' '''apply''' ''matrix'': applies the 2D ''matrix'' transformation to the whole ''pathName''. ''pathName'' '''fitTo''' ''x'' ''y'' ''w'' ''h'': fits (scale&translate) the whole ''pathName'' into the given rect. ''pathName'' '''moveTo''' ''point0'': sets the starting ''point0'' (expressed as a list of two numbers) for the next commands .. ''pathName'' '''lineTo''' ''point'': ''pathName'' '''quadTo''' ''point1'' ''point2'': ''pathName'' '''cubicTo''' ''point1'' ''point2'' ''point3'': ''pathName'' '''smoothQuadTo''' ''point2'': ''pathName'' '''smoothCubicTo''' ''point2'' ''point3'': ''pathName'' '''arcQuadrantTo''' ''point1'' ''point2'': ''pathName'' '''arcTo''' ''pointC'' ''pointR'' ''start'' ''sweep'' ?'''-moveto''' ''boolean''?: ''pathName'' '''ellipticArcTo''' ''point1'' ''pointR'' ''rotation'' ''largeArcFlag'' ''sweepFlag'' ''point1'': ''pathName'' '''close''': ''pathName'' '''reset''': ''pathName'' '''shrink''': shrinks the internal capacity of the path to fit the current usage. ''pathName'' '''bbox''': Get the path's bounding-box. Note that bbox does not consider the line-width, offset, caps (these parameters are definied when stroking/filling the path). If path is empty returns '''{0.0 0.0 0.0 0.0}''' ''pathName'' '''view''': Returns the path data in SVG format ''pathName'' '''contour''': returns the number of countours. ''pathName'' '''contour''' ''i''|'''*''': returns the number of simple curves of the i-th contour. If '''*''' is specified, return a list with the number of simple curves of every contour. ''pathName'' '''contour''' ''i''|'''*''' ''j''|'''*''' ''OP'' ''t'': by using the parametric equation B(t) of the j-th curve of the i-th contour, evaluates one of the following ''OP'' functions at value ''t'' (''t'' must be between 0.0 and 1.0): * '''at''': returns the position {x y} at B(t) * '''tangent''': returns the tangent versor {x y} at B(t) * '''normal''': returns the normal versor {x y} at B(t) * '''tangentAt''': returns the the position and the tangent versor at B(t) * '''normalAt''': returns the the position and the normal versor at B(t) If '''*''' is specified instead of the contour index, this command returns a list with all the ''OP'' evaluations at ''t'' for the j-th curves of every contour. If some contour has less than j curves, its evaluation is {}. If '''*''' is specified instead of the curve index, this command returns a list with all the ''OP'' evaluations at ''t'' for every curve of the i-th contour. If '''*''' is specified for both the contour index and the curve index,this command returns a list of list, i.e. for every contours returns a list of the evaluations of ''OP'' at ''t'' for every its single curve. **BL::FontFace, BL::Font and Glyphs** '' Note: Currently text support is still basic and subject to changes. '' Before drawing some text, you need to load some fonts from an external font-file. '''BL::FontFace''' '''create''' ''faceName'' ''fontfile'' ?''faceIdx''?: loads a ''fontfile'' and creates a new instance of the class '''BL::FontFace''' named ''faceName''. If ''fontfile'' is a font collection, you can specify which fontface to load. Default value for ''faceIdx'' is 0 (i.e. the first fontface). if ''faceIdx'' is greater than the number of the available fontfaces, the last fontface is loaded, and it can be inspected with the '''detail''' method. '''BL::FontFace''' '''new''' ''fontfile'' ?''faceIdx''?: loads a ''fontfile'', creates a new instance of the class '''BL::FontFace''' returning a new unique ''faceName''. ''faceName'' '''destroy''': destroys ''faceName''. Note that in general any oo-object like ''faceName'' should be explicitly destroyed '''BL::FontFace''' '''names''': returns the list of all the currently allocated fontfaces. ''faceName'' '''details''': returns a dictionary with someproperties of the loaded ''faceName''. These are the currently listed properties ;more properties may be added in future Blend2d releases. ====== # load the last fontface from a fontfile-collection # ("AmericanTypewriter.ttc" can be found in the tclBlend2d-devkit distribution ) # Note that I want to load the last fontface, so I specify a large 'faceIdx' # surely greater than the available fontface (.. there're 6 fontfaces in this collection ..) set fface [BL::FontFace new "./AmericanTypewriter.ttc" 999] # pretty print details dict for {key value} [$fface details] { puts "[format "%25s %s" $key $value]" } # .... # other ops ... # $fface destroy ====== This produces the following output : ====== faceIndex 5 glyphCount 916 fullName American Typewriter Condensed Light familyName American Typewriter subfamilyName Condensed Light postScriptName AmericanTypewriter-CondensedLight unitsPerEm 1000 weight 300 style 0 stretch 3 hasCharToGlyphMapping 1 ====== Once a '''BL::FontFace''' has been loaded,and before drawing some text or extracting some glyphs, you should create a '''BL::Font''' object based on an instance of '''BL::FontFace''' '''BL::Font''' '''create''' ''fontName'' ''faceName'' ''fontsize'': creates a new instance of the class '''BL::Font''', based on ''faceName'', having size ''fontsize'' (float). Note that although any text and glyph can be arbitrarialy scaled with the usual 2D trasnsformations, ''fontsize'' can be used to select some special glyphs that some fonts may make available for working with very small font sizes. '''BL::Font''' '''new''' ''faceName'' ''fontsize'': creates a new instance of the class '''BL::Font''' returning a new unique ''fontName''. ''fontName'' '''destroy''': destroys ''fontName''. Note that in general any oo-object like ''fontName'' should be explicitly destroyed '''BL::Font''' '''names''': returns the list of all the currently allocated fonts. A ''fontName'' can be used for drawing some text like in the following example ====== set fontFace [BL::FontFace new "./Arial.ttf"] set fontName [BL::Font $fontFace 12.0] set sfc [BL::Surface new] $sfc fill [BL::text {100 100} $fontName "Hello World"] -style [BL::color orange] ====== but it can also used for extracting single glyphs from it. ''fontName'' '''glyphs''' ''someText'': returns a list of glyph-indexes, one glyph-index for each (Unicode) character in ''someText''. ''fontName'' '''glyph''' ''glyphIdx'': returns a new instance of '''BL::Path''' containing the geometrical representation of the given ''glyphIdx''. Raise an error if ''glyphIdx'' is invalid. Note: this method creates a new '''BL::Path'''instance, and it is user's responsability to destroy it explicitly. Before drawing some text (or a single glyph) you should load a ''fontfile'', then setup a '''BL::Font''' with a given size ====== set aFontFace [BL::FontFace new _fontfile_] set aFont [BL::Font new $aFontFace _size_] ====== note that both '''BL:FontFace''' and '''BL::Font''' create new objects, and therefore it's programmer's responsability to delete them (e.g call "\$aFontFace destroy" ) The easiest way to draw a text on a '''Surface''' is to use the special 'geometry' '''BL::text''' with the fill/stroke methods ====== surfaceName fill [BL::text {10 20} $aFont "Hello World!!"] ====== Of course you can set the drawing-properties of the Surface as usual (color, gradient,line width, matrix transformation ....) Alternatively, you can extract a single glyph from a font, store them as a '''BL::Path''', and then manipulate it as usual ====== set aGlyph [$font glyph 44] ;# extract glyph n.44 $sfc stroke $aGlyph ====== Note that the '''glyph''' methods returns a new '''BL::Path''' object,and therefore it is programmer's responsability to free the resources (e.g. "$aGlyph destroy" ) **Exchanging pixmaps** Blend2d provides commands for loading graphics files in a Surface, as well for saving the Surface's internal framebuffer in a graphic file. Blend2d provides commands for copying (part of) the internal framebuffer among different Surfaces. If the Tk support is loaded, that is if you loaded the '''Blend2d''' or '''tkBlend2d''', you can also exchange parts of the Surfaces framebuffer with tk '''photo''' images. ***read/write files*** ''sfcName'' '''load''' ''filename'': loads the contents of ''filename''. Supported formats: png, jpeg, bmp. WARNING: the internal framebuffer is resized. ''sfcName'' '''save''' ''filename'' ?'''-format''' ''file-format''?: saves the internal framebuffer in ''filename'' If '''-format''' is not specified, this command tries to guess the ''file-format'' from the file extension. NOTE: currently only BMP encoder is available ***copy among surfaces*** ''sfcName'' '''copy''' ''srcSurface'' ?'''-from''' ''{x0 y0 w h}''? ?'''-to''' ''{xp yp}''? ?'''-compop''' ''op''? ?'''-globalalpha''' ''alpha''?: ''sfcName'' '''copy''' ''srcSurface'' ?'''-from''' ''{x0 y0 w h}''? ?'''-to''' ''{x y w h}''? ?'''-compop''' ''op''? ?'''-globalalpha''' ''alpha''?: copies (a sub-region of) ''srcSurface'' to the current ''sfcName''. If no options are specified, this command copies the whole ''srcSurface'' starting at coordinates (0,0). The following options may be specified: '''-from''' ''{x y w h}'': specifies a rectangular sub-region of the surface to be copied. The pixels copied will include the left and top edges of the specified rectangle but not the bottom or right edges. If the '''-from''' option is not given, the default is the whole surface. '''-to''' ''{x y}'': specifies where to place the source sub-region in the current surface. The current surface is never resized, therefore, all parts of the ''srcSurface'' that will be placed outside this surface will be excluded (clipped). '''-to''' ''{x y w h}'': specifies a rectangular sub-region of the current surface. The source sub-region is scaled to fit into destination rectangle. '''-compop''' ''value'': applis a composition-opration to the pixels that will be copied. If this option is not specified, the current value of the '''-compop''' option is used. '''-globalalpha''' ''alpha'': ''srcSurface'' will be blitted using ''alpha'' transparency. If this option is not specified, the current value of the '''-globalalpha''' option is used. Note that if there's a matrix-trasformation (rotation, scaling, ..) on the current surface, this transformation will be applied to all points of the destination sub-region (i.e. the '''-from''' rectangle will be rotated, scaled, ...) ***reading/writing tkphoto*** These commands require the "Blend2d" or "tkBlend2d" package. These commands are not available if you loaded the "tclBlend2d" package; ''sfcName'' '''readFromTkphoto''' ''tkphoto'' ?'''-from''' ''{x0 y0 w h}''? ?'''-to''' ''{x0 y0 w h}''?: copies (a sub-region of) ''tkphoto'' to the current ''sfcName''. If no options are specified, this command copies the whole ''srcSurface'' starting at coordinates (0,0). NOTE: ''sfcName'' is not resized; you should take care to resize it in order to get all the portion of the tkphoto you are interested in. ''sfcName'' '''writeToTkphoto''' ''tkphoto'' ?'''-from''' ''{x0 y0 w h}''? ?'''-to''' ''{x0 y0 w h}''?: copies (a sub-region of) ''sfcName'' to the current ''sfcName''. If no options are specified, this command copies the whole ''srcSurface'' starting at coordinates (0,0). **Creating a blend2d (tk-)image** These commands require the "Blend2d" or "tkBlend2d" package. These commands are not available if you loaded the "tclBlend2d" package; '''image''' '''create''' '''blend2d''' ?''name''? ?''options''?: Similar to the standard command "'''image create photo ...'''", this command creates a new image of type '''blend2d''' plus a new surface-object that can be used for manipulating the image. Options are the same options used for the "'''BL::Surface create ..'''" command. The image can then be embedded in a widget (like a "label" or a "canvas"); every command like '''fill''', '''stroke''' issued to the image name, will immediately change the displayed image. Both "'''image delete sfcName'''" and "''sfcName'' '''destroy'''" can be used to delete the image AND the related surface-object. **Other BL:: commands** '''BL::classes''' : lists the name of the BL classes (e.g BL::Surface,BL::Path, ...) '''BL::classinfo''' ''objectName'': returns the class name of ''objectName''. ''objectName'' can be any '''tcloo''' object (not limited to BL:: objects) '''BL::codecs''' : lists the supported graphics file formats. For each supported graphic file formats, returns a detailed list made of 5 elements: '''id''', '''vendor''', '''mimeType''', '''extensions''', '''features'''. * '''id''' is the key element to be used in load/save operations (e.g. JPEG) * '''vendor''' is the name of the codec's vendor. * '''mimetype''' is a string (e.g. image/jpeg) * '''extensions''' is a sequence of recognized filename-extensions; elements are separated by "|" (e.g. jpg|jpeg|jif|jfi|jfif) * '''features''' is a list of supported features * '''READ''': reading is supported * '''WRITE''': writing is supported * '''LOSSY''': loosy compression * '''LOSSLESS''': lossless compression * '''MULTI_FRAME''': multiple frames (GIF). * '''IPTC''': supported IPTC metadata. * '''EXIF''': supported EXIF metadata. * '''XMP''': supported XMP metadata. '''BL::enum''' : lists all the enum categories '''BL::enum''' ''category'': lists all the values for that _category_ e.g. BL::enum GRADIENT_TYPE --> LINEAR RADIAL CONICAL '''BL::libinfo''' : returns a dictionary with info about the core Blend2d library. The dictionary keys are '''version''', '''type''' (build-type) '''BL::platform''' : returns a dictionary with info about the cpu architecture and the cpu features used by Blend2d. The dictionary keys are '''cpuArch''', '''cpuFeatures''', '''coreCount'''. **Auxiliary utilities** Blend2d provides some small helpers for working with transformation-matrix and colors ***Affine matrix*** An affine matrix is a 3x3 matrix whose last column is fixed 0 0 1 ====== a b 0 c d 0 e f 1 ====== Given this rule it is convenient to express such matrices as a list of 6 numbers { a b c d e f } instead of 9 numbers. Working with these matrices can be simplified by using the '''Mtx''' package included in Blend2D. In the following paragraphs "M" stands for a matrix (a list of 6 numbers), "P" stands for a 2D point (a list of 2 numbers). The following ops are supported '''Mtx::identity''' : returns the identity matrix '''{1 0 0 1 0 0}''' '''Mtx::MxM''' ''M1'' ''M2'': matrix multiplication '''Mtx::determinant''' ''M'': '''Mtx::invert''' ''M'': matrix inversion - Raise an error if ''M'' is not inverible. '''Mtx::PxM''' ''P'' ''M'': map a Point '''Mtx::multiPxM''' ''Points'' ''M'': map a list of Points '''Mtx::P-P''' ''P1'' ''P2'': return P1-P2 '''Mtx::VxM''' ''V'' ''M'': map a vector ''V'' : VxM(V,M) = PxM(V,M)-PxM(0,M) '''Mtx::translation''' ''dx'' ''dy'': '''Mtx::scale''' ''sx'' ?''sx''? ?''C''?: scale sx sy around the fixed-point C '''Mtx::rotation''' ''angle'' '''radians'''|'''degrees''' ?''C''?: performs a rotation of ''angle'' around the fixex-point ''C'' '''Mtx::skew''' ''sx'' ''sy'': '''Mtx::xreflection''' : '''Mtx::yreflection''' : '''Mtx::translate''' ''M'' ''dx'' ''dy'': '''Mtx::post_translate''' ''M'' ''dx'' ''dy'': '''Mtx::scaling''' ''M'' ''sx'' ''sy'' ?''C''?: '''Mtx::post_scaling''' ''M'' ''sx'' ''sy'' ?''C''?: '''Mtx::rotate''' ''M'' ''angle'' '''radians'''|'''degrees''' ?''C''?: '''Mtx::post_rotate''' ''M'' ''angle'' '''radians'''|'''degrees''' ?''C''?: '''Mtx::yreflect''' ''M'': ***HSB color model*** Blend2d internally works with colors expressed in terms of red,green,blue and alpha channels, but in same cases it is more natural to express color following the HSB color model, where: * h (hue) is a 0.0..360.0 angle * s (saturation) is 0.0 .. 1.0 * b (brigthess) is 0.0 .. 1.0 ( 0 is black, 1 is white ) The following commands are availables for converting between between ARGB and HSB color models. alpha is 0.0 .. 1.0 '''HSB''' ''h'' ''s'' ''b'' ?''alpha''?: returns an ARGB number (in decimal notation, not in hex notation) '''RGB2HSB''' ''0xAARRGGBB'': returns a list with the HSB components. { h s b alpha } **Limitations** * Saving a Surface is currently limited to BMP files. * The '''-stroke.dasharray''' option is currently a no-op. **KEYWORDS** graphics **CATEGORY** vector grahics **COPYRIGHT** Copyright (c) 2020, by A.Buratti <> ---- ---- ---- <> Old Stuff [ABU] 12-Jul-2020 TclTk binding for Blend2d is almost ready .. Just some fixing for the last Blend2d features (multithread rendering) and for a more tcl-ish API. In the meantime you can play with the new [pixmix] 2.x demos. [pixmix] includes a preliminary tcl-Blend2d engine and, although Blend2d is a vector graphics engine, it provides amazing performances even for working with large (fullscreen) bitmaps. ---- [ABU] 18-Oct-2019 Blend2D is a high performance 2D vector graphics engine. See https://blend2d.com [Image: Blend2d composition] Credits to https://ciechanow.ski/alpha-compositing/ ---- TclTk binding is still at alpha stage, performances are amazing. Here is a demo screenshot. Rotation/zoom at full screen resolution in real-time (no flickering) [Blend2d-Tiger] [Blend2 -sketcking] More to come.. <> ---- '''[arjen] - 2020-07-17 09:43:26''' Very nice - I followed the instructions and it works as described :). Haven't tried anything complicated yet, but this is encouraging. [ABU] Thanks. I'm going to write a better reference manual and a sort of tutorial. Let me know what sounds complicated.. ---- '''[arjen] - 2020-07-20 06:40:52''' Wrt "complicated": I merely meant that I varied on some of the commands in the documentation and this page to see how things work. And I had a look at the demos. Esecially rotating the tiger image was impressive.