license

2024-06-26 23:26:42 -04:00
parent f08b04e901
commit 063cf6b45c
4 changed files with 153 additions and 1 deletions
--- a/code/font/VEFontCache/LICENSE.md
+++ b/code/font/VEFontCache/LICENSE.md
@@ -0,0 +1,21 @@
+VEFontCache Odin Version
+Copyright 2024 Edward R. Gonzalez
+
+This project is based on Vertex Engine GPU Font Cache
+by Xi Chen (https://github.com/hypernewbie/VEFontCache). It has been substantially
+rewritten and redesigned for the Odin programming language.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial
+portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
+OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
--- a/code/font/VEFontCache/docs/original/LICENSE.md
+++ b/code/font/VEFontCache/docs/original/LICENSE.md
@@ -0,0 +1,17 @@
+Vertex Engine GPU Font Cache
+Copyright 2020 Xi Chen
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial
+portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
+OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
--- a/code/font/VEFontCache/docs/original/README.md
+++ b/code/font/VEFontCache/docs/original/README.md
@@ -0,0 +1,114 @@
+# Notice
+
+This is the original readme fo the C++ implementation by Xi Chen.
+
+# VE Font Cache is a single header-only GPU font rendering library designed for game engines.
+
+It aims to:
+ * Be fast and simple to integrate.
+ * Take advantage of modern GPU power.
+ * Be backend agnostic and easy to port to any API such as Vulkan, DirectX, OpenGL.
+ * Load TTF & OTF file formats directly.
+ * Use only runtime cache with no offline calculation.
+ * Render glyphs at reasonable quality at a wide range of font sizes.
+ * Support a good amount of internationalisation. そうですね!
+ * Support cached text shaping with HarfBuzz with simple Latin-style fallback.
+ * Load and unload fonts at any time.
+
+# How it works
+
+Glyphs are GPU rasterised with 16x supersampling. This method is a simplification of "Easy Scalable Text Rendering on the GPU",
+by Evan Wallace, making use of XOR blending. Bézier curves are handled via brute force triangle tessellation; even 6 triangles per
+curve only generates < 300 triangles, which is nothing for modern GPUs! This avoids complex frag shader for reasonable quality.
+
+![Wireframe with GPU XOR blending](images/wireframe.png)
+
+Texture atlas caching uses naïve grid placement; this wastes a lot of space but ensures interchangeable cache slots allowing for
+straight up LRU ( Least Recently Used ) caching scheme to be employed.
+
+The font atlas is a single 4k x 2k R8 texture divided into 4 regions:
+
+```
+     2k
+     --------------------
+     |         |        |
+     |    A    |        |
+     |         |        | 2
+     |---------|    C   | k  
+     |         |        |
+  1k |    B    |        |
+     |         |        |
+     --------------------
+     |                  |
+     |                  |
+     |                  | 2
+     |        D         | k  
+     |                  |
+     |                  |
+     |                  |
+     --------------------        
+               
+     Region A = 32x32 caches, 1024 glyphs
+     Region B = 32x64 caches, 512 glyphs
+     Region C = 64x64 caches, 512 glyphs
+     Region D = 128x128 caches, 256 glyphs
+```
+
+Region A is designed for small glyphs, Region B is for tall glyphs, Region C is for large glyphs, and Region D for huge glyphs.
+Glyphs are first rendered to an intermediate 2k x 512px R8 texture. This allows for minimum 4 Region D glyphs supersampled at
+4 x 4 = 16x supersampling, and 8 Region C glyphs similarly. A simple 16-tap box downsample shader is then used to blit from this
+intermediate texture to the final atlas location.
+
+The atlas texture looks something like this:
+![Wireframe with GPU XOR blending](images/atlas_small.png)
+
+# Usage
+
+Pseudo-code demonstrating simple usage:
+```cpp
+#define VE_FONTCACHE_IMPL
+#include "../ve_fontcache.h"
+
+static std::vector< uint8_t > buffer;
+ve_fontcache_init( &cache );
+ve_fontcache_configure_snap( &cache, width, height );
+print_font = ve_fontcache_loadfile( &cache, "fonts/NotoSansJP-Light.otf", buffer, 19.0f );
+ve_fontcache_draw_text( &cache, print_font, u8"hello world", 0, 0, 1.0f / width,  1.0f / height );
+```
+
+These header files need to be copied to your project:
+```
+ve_fontcache.h
+utf8.h
+stb_truetype.h
+```
+
+Except HarfBuzz, that's all the required dependencies. That said it's strongly recommended
+to use HarfBuzz ( TODO: HarfBuzz not supported yet, coming soon!! ) over the default utf8.h latin
+fallback text shaper.
+
+## Integration with rendering backend
+
+VEFontCache is largely backend agnostic. Currently the demo project uses OpenGL 3.3 for Windows.
+That said it's designed to be integrated with VE, a Vulkan engine.
+Please read the "How to plug into rendering API" section in ve_fontcache.h for more documentation
+on how to implement your own backend to plumb this directly into your engine!
+
+# Screenshots
+
+![Screenshot 1](images/ve_fontcache_demo1.png)
+
+![Screenshot 2](images/ve_fontcache_demo2.png)
+
+![Screenshot 3](images/raincode.png)
+
+![Screenshot 4](images/ve_fontcache_pressure_test.gif)
+
+# Similar projects and links
+
+Here are links to some awesome similar and related projects:
+* fontstash - https://github.com/memononen/fontstash
+* stb_truetype ( has font rasterisation itself ) - https://github.com/nothings/stb/blob/master/stb_truetype.h
+* slug - http://sluglibrary.com/
+* pathfinder - https://github.com/pcwalton/pathfinder
+* https://medium.com/@evanwallace/easy-scalable-text-rendering-on-the-gpu-c3f4d782c5ac
--- a/code/font/VEFontCache/draw.odin
+++ b/code/font/VEFontCache/draw.odin
@@ -219,7 +219,7 @@ cache_glyph_to_atlas :: proc( ctx : ^Context,
 	region      : ^AtlasRegion,
 	over_sample : Vec2 )
 {
-	profile(#procedure)
+	// profile(#procedure)

 	// Get hb_font text metrics. These are unscaled!
 	bounds_0, bounds_1 := parser_get_glyph_box( & entry.parser_info, glyph_index )