bug 900199 - Add OpenGL registry xml parser to generate constants - step 1 - r=bjacob,jgilbert,jrmuizel

gfx/gl/GLParseRegistryXML.py

@@ -0,0 +1,212 @@
+#!/usr/bin/env python
+# coding=utf8
+
+
+################################################################################
+# TUTORIAL
+# This script will generate GLConsts.h
+#
+# Step 1:
+#   Download the last gl.xml, egl.xml, glx.xml and wgl.xml from
+#   http://www.opengl.org/registry/#specfiles into a directory of your choice
+#
+# Step 2:
+#   Execute this script ./GLParseRegistryXML.py [your dir containing XML files]
+#
+# Step 3:
+#   Do not add the downloaded XML in the patch
+#
+# Step 4:
+#   Enjoy =)
+#
+################################################################################
+
+# includes
+import os
+import sys
+import xml.etree.ElementTree
+
+
+################################################################################
+# export management
+
+class GLConstHeader:
+    def __init__(self, f):
+        self.f = f
+
+
+    def write(self, arg):
+        if isinstance(arg, list):
+            self.f.write('\n'.join(arg) + '\n')
+        elif isinstance(arg, (int, long)):
+            self.f.write('\n' * arg)
+        else:
+            self.f.write(str(arg) + '\n')
+
+
+    def formatFileBegin(self):
+        self.write([
+                    '/* This Source Code Form is subject to the terms of the Mozilla Public',
+                    ' * License, v. 2.0. If a copy of the MPL was not distributed with this',
+                    ' * file, You can obtain one at http://mozilla.org/MPL/2.0/. */',
+                    '',
+                    '#if !defined(GLCONSTS_H_)',
+                    '#define GLCONSTS_H_',
+                    '',
+                    '/**',
+                    ' * GENERATED FILE, DO NOT MODIFY DIRECTLY.',
+                    ' * THIS IS A GENERATED FILE DIRECTLY FROM THE OFFCIAL OPENGL REGISTRY',
+                    ' * XML AVAILABLE AT http://www.opengl.org/registry/#specfiles.',
+                    ' *',
+                    ' * To generate this file, see tutorial in GLParseRegistry.py',
+                    ' */',
+                    ''
+                   ])
+
+
+    def formatLibBegin(self, lib):
+        # lib would be 'GL', 'EGL', 'GLX' or 'WGL'
+        self.write('// ' + lib)
+
+
+    def formatLibConstant(self, lib, name, value):
+        # lib would be 'GL', 'EGL', 'GLX' or 'WGL'
+        # name is the name of the const (example: MAX_TEXTURE_SIZE)
+        # value is the value of the const (example: 0xABCD)
+
+        define = '#define LOCAL_' + lib + '_' + name
+        whitespace = max(60 - len(define), 0)
+        self.write(define + ' ' * whitespace + ' ' + value)
+
+
+    def formatLibEnd(self, lib):
+        # lib would be 'GL', 'EGL', 'GLX' or 'WGL'
+        self.write(2)
+
+
+    def formatFileEnd(self):
+        self.write([
+                    '',
+                    '#endif // GLCONSTS_H_'
+                   ])
+
+
+################################################################################
+# underground code
+
+def getScriptDir():
+    return os.path.dirname(__file__) + '/'
+
+
+def getXMLDir():
+    if len(sys.argv) == 1:
+        return './'
+
+    dirPath = sys.argv[1]
+    if dirPath[-1] != '/':
+        dirPath += '/'
+
+    return dirPath
+
+
+class GLConst:
+    def __init__(self, lib, name, value, type):
+        self.lib = lib
+        self.name = name
+        self.value = value
+        self.type = type
+
+
+class GLDatabase:
+
+    LIBS = ['GL', 'EGL', 'GLX', 'WGL']
+
+    def __init__(self):
+        self.consts = {}
+        self.libs = set(GLDatabase.LIBS)
+        self.vendors = set(['EXT', 'ATI'])
+        # there is no vendor="EXT" and vendor="ATI" in gl.xml,
+        # so we manualy declare them
+
+
+    def loadXML(self, path):
+        xmlPath = getXMLDir() + path
+
+        if not os.path.isfile(xmlPath):
+            print 'missing file "' + xmlPath + '"'
+            return False
+
+        tree = xml.etree.ElementTree.parse(xmlPath)
+        root = tree.getroot()
+
+        for enums in root.iter('enums'):
+            vendor = enums.get('vendor')
+            if not vendor:
+                # there some standart enums that do have the vendor attribute,
+                # so we fake them as ARB's enums
+                vendor = 'ARB'
+
+            if vendor not in self.vendors:
+                # we map this new vendor in the vendors set.
+                self.vendors.add(vendor)
+
+            namespaceType = enums.get('type')
+
+            for enum in enums:
+                if enum.tag != 'enum':
+                    # this is not an enum => we skip it
+                    continue
+
+                lib = enum.get('name').split('_')[0]
+
+                if lib not in self.libs:
+                    # unknown library => we skip it
+                    continue
+
+                name = enum.get('name')[len(lib) + 1:]
+                value = enum.get('value')
+                type = enum.get('type')
+
+                if not type:
+                    # if no type specified, we get the namespace's default type
+                    type = namespaceType
+
+                self.consts[lib + '_' + name] = GLConst(lib, name, value, type)
+
+        return True
+
+
+    def exportConsts(self, path):
+        with open(getScriptDir() + path,'w') as f:
+
+            headerFile = GLConstHeader(f)
+            headerFile.formatFileBegin()
+
+            constNames = self.consts.keys()
+            constNames.sort()
+
+            for lib in GLDatabase.LIBS:
+                headerFile.formatLibBegin(lib)
+
+                for constName in constNames:
+                    const = self.consts[constName]
+
+                    if const.lib != lib:
+                        continue
+
+                    headerFile.formatLibConstant(lib, const.name, const.value)
+
+                headerFile.formatLibEnd(lib)
+
+            headerFile.formatFileEnd()
+
+
+glDatabase = GLDatabase()
+
+success = glDatabase.loadXML('gl.xml')
+success = success and glDatabase.loadXML('egl.xml')
+success = success and glDatabase.loadXML('glx.xml')
+success = success and glDatabase.loadXML('wgl.xml')
+
+if success:
+    glDatabase.exportConsts('GLConsts.h')