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