gfx/gl/GLConsts.py

   1 #!/usr/bin/env python3
   2
   3 """
   4 This script will regenerate and update GLConsts.h.
   5
   6 Step 1:
   7   Download the last gl.xml, egl.xml, glx.xml and wgl.xml from
   8   http://www.opengl.org/registry/#specfiles into some XML_DIR:
   9     wget https://www.khronos.org/registry/OpenGL/xml/gl.xml
  10     wget https://www.khronos.org/registry/OpenGL/xml/glx.xml
  11     wget https://www.khronos.org/registry/OpenGL/xml/wgl.xml
  12     wget https://www.khronos.org/registry/EGL/api/egl.xml
  13
  14 Step 2:
  15   `py ./GLConsts.py <XML_DIR>`
  16
  17 Step 3:
  18   Do not add the downloaded XML in the patch
  19
  20 Step 4:
  21   Enjoy =)
  22 """
  23
  24 # includes
  25 import pathlib
  26 import sys
  27 import xml.etree.ElementTree
  28 from typing import List  # mypy!
  29
  30 # -
  31
  32 (_, XML_DIR_STR) = sys.argv
  33 XML_DIR = pathlib.Path(XML_DIR_STR)
  34
  35 # -
  36
  37 HEADER = b"""
  38 /* This Source Code Form is subject to the terms of the Mozilla Public
  39  * License, v. 2.0. If a copy of the MPL was not distributed with this
  40  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
  41
  42 // clang-format off
  43
  44 #ifndef GLCONSTS_H_
  45 #define GLCONSTS_H_
  46
  47 /**
  48  * GENERATED FILE, DO NOT MODIFY DIRECTLY.
  49  * This is a file generated directly from the official OpenGL registry
  50  * xml available http://www.opengl.org/registry/#specfiles.
  51  *
  52  * To generate this file, see tutorial in \'GLConsts.py\'.
  53  */
  54 """[
  55     1:
  56 ]
  57
  58 FOOTER = b"""
  59 #endif // GLCONSTS_H_
  60
  61 // clang-format on
  62 """[
  63     1:
  64 ]
  65
  66 # -
  67
  68
  69 def format_lib_constant(lib, name, value):
  70     # lib would be 'GL', 'EGL', 'GLX' or 'WGL'
  71     # name is the name of the const (example: MAX_TEXTURE_SIZE)
  72     # value is the value of the const (example: 0xABCD)
  73
  74     define = "#define LOCAL_" + lib + "_" + name
  75     whitespace = 60 - len(define)
  76     if whitespace < 0:
  77         whitespace = whitespace % 8
  78
  79     return define + " " * whitespace + " " + value
  80
  81
  82 class GLConst:
  83     def __init__(self, lib, name, value, type):
  84         self.lib = lib
  85         self.name = name
  86         self.value = value
  87         self.type = type
  88
  89
  90 class GLDatabase:
  91     LIBS = ["GL", "EGL", "GLX", "WGL"]
  92
  93     def __init__(self):
  94         self.consts = {}
  95         self.libs = set(GLDatabase.LIBS)
  96         self.vendors = set(["EXT", "ATI"])
  97         # there is no vendor="EXT" and vendor="ATI" in gl.xml,
  98         # so we manualy declare them
  99
 100     def load_xml(self, xml_path):
 101         tree = xml.etree.ElementTree.parse(xml_path)
 102         root = tree.getroot()
 103
 104         for enums in root.iter("enums"):
 105             vendor = enums.get("vendor")
 106             if not vendor:
 107                 # there some standart enums that do have the vendor attribute,
 108                 # so we fake them as ARB's enums
 109                 vendor = "ARB"
 110
 111             if vendor not in self.vendors:
 112                 # we map this new vendor in the vendors set.
 113                 self.vendors.add(vendor)
 114
 115             namespaceType = enums.get("type")
 116
 117             for enum in enums:
 118                 if enum.tag != "enum":
 119                     # this is not an enum => we skip it
 120                     continue
 121
 122                 lib = enum.get("name").split("_")[0]
 123
 124                 if lib not in self.libs:
 125                     # unknown library => we skip it
 126                     continue
 127
 128                 name = enum.get("name")[len(lib) + 1 :]
 129                 value = enum.get("value")
 130                 type = enum.get("type")
 131
 132                 if not type:
 133                     # if no type specified, we get the namespace's default type
 134                     type = namespaceType
 135
 136                 self.consts[lib + "_" + name] = GLConst(lib, name, value, type)
 137
 138
 139 # -
 140
 141 db = GLDatabase()
 142 db.load_xml(XML_DIR / "gl.xml")
 143 db.load_xml(XML_DIR / "glx.xml")
 144 db.load_xml(XML_DIR / "wgl.xml")
 145 db.load_xml(XML_DIR / "egl.xml")
 146
 147 # -
 148
 149 lines: List[str] = []  # noqa: E999 (bug 1573737)
 150
 151 keys = sorted(db.consts.keys())
 152
 153 for lib in db.LIBS:
 154     lines.append("// " + lib)
 155
 156     for k in keys:
 157         const = db.consts[k]
 158
 159         if const.lib != lib:
 160             continue
 161
 162         const_str = format_lib_constant(lib, const.name, const.value)
 163         lines.append(const_str)
 164
 165     lines.append("")
 166
 167 # -
 168
 169 b_lines: List[bytes] = [HEADER] + [x.encode() for x in lines] + [FOOTER]
 170 b_data: bytes = b"\n".join(b_lines)
 171
 172 dest = pathlib.Path("GLConsts.h")
 173 dest.write_bytes(b_data)
 174
 175 print(f"Wrote {len(b_data)} bytes.")  # Some indication that we're successful.