ShivaVG

See AUTHORS for the list of contributors

ShivaVG is an open-source LGPL ANSI C implementation of the Khronos Group OpenVG specification.

I. BUILD II. TESTING III. IMPLEMENTATION STATUS IV. EXTENSIONS

I. BUILD

• Prerequisites:

  OpenGL development libraries and headers should be installed. Othe than that, since it's ANSI C should compile with any modern C compiler. jpeglib needs to be installed for example programs that use images.

• Compiling under UNIX systems:

  Read the INSTALL file for more detailed (though generic) directions. This library uses the standard ./configure ; make. The example programs are automatically compiled. However, compilation of each example program can be toggled by ./configure --with-example-xxx command where xxx denotes the name of the example. Run ./configure --help for a list of such options.

• Compiling on Mac:

  No XCode project files provided yet. The easiest way is by just using gcc, in which case look under UNIX compiling section.

• Compiling natively on Windows platform:

  Solution files are provided for Visual C++ version 7 and 8. For the example programs using images to compile, you will need the appropriate build of jpeglib to match your Visual C++ version.

• Compiling in mingw / cygwin environment:

  Might work just as fine as any UNIX-flavored system, but hasn't been tested yet.

II. TESTING

There is no real testing suite yet. The example programs are there just to play with what the implementation can currently do, but can hardly provide any proper validation, since no reference images are provided. Here is a description of each example program and what features it highlights:

• test_vgu

  Constructs some path primitives using the VGU API.

• test_tiger

  The most simple performance test. It draws the well known svg tiger using just simple stroke and fill of solid colors. It consists of 240 paths.

• test_dash

  Shows different stroke dashing modes.

• test_linear

  A rectangle drawn using 3-color linear gradient fill paint

• test_radial

  A rectangle drawn using 3-color radial gradient fill paint

• test_interpolate

  Interpolates between two paths - an apple and a pear.

• test_image

  Images are drawn using VG_DRAW_IMAGE_MULTIPLY image mode to be multiplied with radial gradient fill paint.

• test_pattern

  An image is drawn in multiply mode with an image pattern fill paint.

III. IMPLEMENTATION STATUS

Khronos states in the OpenVG specification, that the contexts for all their client APIs are expected to be created via the EGL API. Since EGL to use with ShivaVG has not been implemented yet, there is a set of extension functions provided for the task of creating, maintaining and destroying the OpenVG context. (See next section EXTENSIONS for details.)

What follows is a description of which functions or to what extent a certain function has been implemented. When a function is marked as PARTIALLY implemented, the TODO file or the comments in the code itself would provide further clues.

• General:

vgGetError ............................ FULLY implemented vgFlush ............................... FULLY implemented vgFinish .............................. FULLY implemented

• Getters and setters:

vgSet ................................. FULLY implemented vgSeti ................................ FULLY implemented vgSetfv ............................... FULLY implemented vgSetiv ............................... FULLY implemented vgGetf ................................ FULLY implemented vgGeti ................................ FULLY implemented vgGetVectorSize ....................... FULLY implemented vgGetfv ............................... FULLY implemented vgGetiv ............................... FULLY implemented vgSetParameterf ....................... FULLY implemented vgSetParameteri ....................... FULLY implemented vgSetParameterfv ...................... FULLY implemented vgSetParameteriv ...................... FULLY implemented vgGetParameterf ....................... FULLY implemented vgGetParameteri ....................... FULLY implemented vgGetParameterVectorSize............... FULLY implemented vgGetParameterfv ...................... FULLY implemented vgGetParameteriv ...................... FULLY implemented

• Matrix Manipulation:

vgLoadIdentity ........................ FULLY implemented vgLoadMatrix .......................... FULLY implemented vgGetMatrix ........................... FULLY implemented vgMultMatrix .......................... FULLY implemented vgTranslate ........................... FULLY implemented vgScale ............................... FULLY implemented vgShear ............................... FULLY implemented vgRotate .............................. FULLY implemented

• Masking and Clearing:

vgMask ................................ NOT implemented vgClear ............................... FULLY implemented

• Paths:

vgCreatePath .......................... FULLY implemented vgClearPath ........................... FULLY implemented vgDestroyPath ......................... FULLY implemented vgRemovePathCapabilities .............. FULLY implemented vgGetPathCapabilities ................. FULLY implemented vgAppendPath .......................... FULLY implemented vgAppendPathData ...................... FULLY implemented vgModifyPathCoords .................... FULLY implemented vgTransformPath ....................... FULLY implemented vgInterpolatePath ..................... FULLY implemented vgPathLength .......................... NOT implemented vgPointAlongPath ...................... NOT implemented vgPathBounds .......................... FULLY implemented vgPathTransformedBounds ............... FULLY implemented vgDrawPath ............................ PARTIALLY implemented

• Paint:

vgCreatePaint ......................... FULLY implemented vgDestroyPaint ........................ FULLY implemented vgSetPaint ............................ FULLY implemented vgGetPaint ............................ FULLY implemented vgSetColor ............................ FULLY implemented vgGetColor ............................ FULLY implemented vgPaintPattern ........................ FULLY implemented

• Images:

vgCreateImage ......................... PARTIALLY implemented vgDestroyImage ........................ FULLY implemented vgClearImage .......................... FULLY implemented vgImageSubData ........................ PARTIALLY implemented vgGetImageSubData ..................... PARTIALLY implemented vgChildImage .......................... NOT implemented vgGetParent ........................... NOT implemented vgCopyImage ........................... FULLY implemented vgDrawImage ........................... PARTIALLY implemented vgSetPixels ........................... FULLY implemented vgWritePixels ......................... FULLY implemented vgGetPixels ........................... FULLY implemented vgReadPixels .......................... FULLY implemented vgCopyPixels .......................... FULLY implemented

• Image Filters:

vgColorMatrix ......................... NOT implemented vgConvolve ............................ NOT implemented vgSeparableConvolve ................... NOT implemented vgGaussianBlur ........................ NOT implemented vgLookup .............................. NOT implemented vgLookupSingle ........................ NOT implemented

• Hardware Queries:

vgHardwareQuery ....................... NOT implemented

• Renderer and Extension Information:

vgGetString ........................... FULLY implemented

• VGU

vguLine ............................... FULLY implemented vguPolygon ............................ FULLY implemented vguRect ............................... FULLY implemented vguRoundRect .......................... FULLY implemented vguEllipse ............................ FULLY implemented vguArc ................................ FULLY implemented vguComputeWarpQuadToSquare ............ NOT implemented vguComputeWarpSquareToQuad ............ NOT implemented vguComputeWarpQuadToQuad .............. NOT implemented

IV. EXTENSIONS

There are three extensions to the API that manipulate the OpenVG context as a temporary replacement for EGL:

VGboolean vgCreateContextSH(VGint width, VGint height)

Creates an OpenVG context on top of an existing OpenGL context that should have been manually initialized by the user of the library. Width and height specify the size of the rendering surface. No multi-threading support has been implemented yet. The context is created once per process.

void vgResizeSurfaceSH(VGint width, VGint height)

Should be called whenever the size of the surface changes (e.g. the owner window of the OpenGL context is resized).

void vgDestroyContextSH()

Destroys the OpenVG context associated with the calling process.