OpenVG Specification Version 1.0.1 Version 1.0 - August 1, 2005 Amended January 26, 2007 Editor: Daniel Rice, Google, Inc. rice@ google.com “ ” For Ilise – DSR Copyright © 2005-2007 The Khronos Group Inc. All Rights Reserved. This specification is protected by copyright laws and contains material proprietary to the Khronos Group, Inc. It or any components may not be reproduced, republished, distributed, transmitted, displayed, broadcast or otherwise exploited in any manner without the express prior written permission of Khronos Group. You may use this specification for implementing the functionality therein, without altering or removing any trademark, copyright or other notice from the specification, but the receipt or possession of this specification does not convey any rights to reproduce, disclose, or distribute its contents, or to manufacture, use, or sell anything that it may describe, in whole or in part. 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Table of Contents 1 Introduction........................................................................................................................................1 1.1 Feature Set................................................................................................................................1 1.2 Target Applications....................................................................................................................1 SVG Viewers..................................................................................................................................1 Portable Mapping Applications..................................................................................................1 E-book Readers..............................................................................................................................2 Games.............................................................................................................................................2 Scalable User Interfaces................................................................................................................2 Low-Level Graphics Device Interface........................................................................................2 1.3 Target Devices..........................................................................................................................2 1.4 Design Philosophy.....................................................................................................................2 1.5 Naming and Typographical Conventions..................................................................................3 1.6 Library Naming..........................................................................................................................3 2 The OpenVG Pipeline........................................................................................................................4 2.1 Stage 1: Path, Transformation, Stroke, and Paint.....................................................................5 2.2 Stage 2: Stroked Path Generation............................................................................................5 2.3 Stage 3: Transformation............................................................................................................5 2.4 Stage 4: Rasterization...............................................................................................................5 2.5 Stage 5: Clipping and Masking.................................................................................................6 2.6 Stage 6: Paint Generation.........................................................................................................6 2.7 Stage 7: Image Interpolation.....................................................................................................6 2.8 Stage 8: Blending and Antialiasing...........................................................................................6 3 Constants, Functions and Data Types..............................................................................................7 3.1 Versioning.................................................................................................................................7 OPENVG_VERSION_1_0............................................................................................................7 3.2 Primitive Data Types.................................................................................................................7 VGbyte............................................................................................................................................7 VGubyte.........................................................................................................................................7 VGshort..........................................................................................................................................7 VGint...............................................................................................................................................8 VGuint............................................................................................................................................8 VGbitfield.......................................................................................................................................8 VGboolean.....................................................................................................................................8 VGfloat...........................................................................................................................................8 3.3 Floating-Point and Integer Representations..............................................................................8 VG_MAXSHORT..........................................................................................................................9 VG_MAXINT.................................................................................................................................9 VG_MAX_FLOAT.........................................................................................................................9 3.4 Colors........................................................................................................................................9 3.4.1 Linear and Non-Linear Color Representations.................................................................9 3.4.2 Color Space Definitions...................................................................................................10 3.4.3 Premultiplied Alpha.........................................................................................................12 3.4.4 Color Format Conversion................................................................................................13 3.5 Enumerated Data Types.........................................................................................................14 3.6 Handle-based Data Types.......................................................................................................15 i VGHandle....................................................................................................................................15 VG_INVALID_HANDLE..........................................................................................................15 4 The Drawing Context.......................................................................................................................16 4.1 Errors.......................................................................................................................................17 VGErrorCode...............................................................................................................................18