1// Copyright 2019-2021 The Khronos Group Inc. 2// 3// SPDX-License-Identifier: CC-BY-4.0 4 5include::{generated}/meta/{refprefix}VK_EXT_line_rasterization.txt[] 6 7=== Other Extension Metadata 8 9*Last Modified Date*:: 10 2019-05-09 11*IP Status*:: 12 No known IP claims. 13*Contributors*:: 14 - Jeff Bolz, NVIDIA 15 - Allen Jensen, NVIDIA 16 - Jason Ekstrand, Intel 17 18=== Description 19 20This extension adds some line rasterization features that are commonly used 21in CAD applications and supported in other APIs like OpenGL. 22Bresenham-style line rasterization is supported, smooth rectangular lines 23(coverage to alpha) are supported, and stippled lines are supported for all 24three line rasterization modes. 25 26include::{generated}/interfaces/VK_EXT_line_rasterization.txt[] 27 28=== Issues 29 30 (1) Do we need to support Bresenham-style and smooth lines with more than 31 one rasterization sample? i.e. the equivalent of glDisable(GL_MULTISAMPLE) 32 in OpenGL when the framebuffer has more than one sample? 33 34 RESOLVED: Yes. 35 For simplicity, Bresenham line rasterization carries forward a few 36 restrictions from OpenGL, such as not supporting per-sample shading, alpha 37 to coverage, or alpha to one. 38 39=== Version History 40 41 * Revision 1, 2019-05-09 (Jeff Bolz) 42 - Initial draft 43