Format of the Cvx BGL Files - Revision history

Szpike: /* Algorithm */ Fixing a minor but critical bug!

2020-10-14T14:45:33Z

Algorithm: Fixing a minor but critical bug!

← Older revision		Revision as of 09:45, 14 October 2020
Line 519:		Line 519:
	ShiftValue = 0 ;		ShiftValue = 0 ;
	NbBytesLeftToRead = ((rootMask * nbPoints) * 2 + 7) >> 3;		NbBytesLeftToRead = ((rootMask * nbPoints) * 2 + 7) >> 3;
	Mask = 1 << rootMask ; /* 2 ^ rootMask */		Mask = (1 << rootMask) - 1; /* 2 ^ rootMask */

	/* Read first value */		/* Read first value */

2014-09-01T20:45:01Z

← Older revision		Revision as of 15:45, 1 September 2014
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	~~{{Infobox-Applicable-FSVersion~~
	~~\| P3D2 = true~~
	~~\| P3D = true~~
	~~\| FSXI = false~~
	~~\| FSXA = true~~
	~~\| FSX = true~~
	~~\| FS2004 = unknown~~
	~~\| FS2002 = unknown~~
	~~\| FS2000 = unknown~~
	~~\| FS98 = unknown~~
	~~\| XP10 = false~~
	~~\| XP9 = false~~
	}}
	= Introduction =		= Introduction =
	cvx*.bgl files can be read by the TmfViewer.exe application provided with the FS SDK. They contain TERRAIN_VECTOR_DB sections. These sections and subsections describe the different layers (roads, railways, water polygons, etc.) along with the geographical coordinates.		cvx*.bgl files can be read by the TmfViewer.exe application provided with the FS SDK. They contain TERRAIN_VECTOR_DB sections. These sections and subsections describe the different layers (roads, railways, water polygons, etc.) along with the geographical coordinates.

2014-09-01T20:44:05Z

Computing the bounding coordinates from a DWORD value

2014-08-28T00:35:13Z

Subsection Header

← Older revision		Revision as of 19:35, 27 August 2014
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	\| 0x04		\| 0x04
	\| 4 - DWORD		\| 4 - DWORD
	\| Bounding coordinates of a squared area covered by this subsection. See [[#~~Annexe A~~\|~~Annexe A~~]].		\| Bounding coordinates of a squared area covered by this subsection. See [[#Computing the bounding coordinates from a DWORD value\|Computing the bounding coordinates from a DWORD value]].
	\|-		\|-
	\| 0x08		\| 0x08

2014-08-28T00:34:52Z

File Header

← Older revision		Revision as of 19:34, 27 August 2014
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	\| Array[8] of unsigned integers (DWORD).<br/>Each value describes the bounding coordinates of a squared subarea.<br/>		\| Array[8] of unsigned integers (DWORD).<br/>Each value describes the bounding coordinates of a squared subarea.<br/>
	Even if 8 slots are provided, it is not necessary to have all 8 values filled. The list stops at the first null (0x00000000) value.<br/>		Even if 8 slots are provided, it is not necessary to have all 8 values filled. The list stops at the first null (0x00000000) value.<br/>
	I don’t know what these subareas are used for.<br/>To compute the bounding coordinates, please see [[#~~Annexe A~~\|~~Annexe A~~]].<br/>To get the bounding coordinates of the square area covered by the file, just keep the minimal and maximal values of each bounding coordinates.		I don’t know what these subareas are used for.<br/>To compute the bounding coordinates, please see [[#Computing the bounding coordinates from a DWORD value\|Computing the bounding coordinates from a DWORD value]].<br/>To get the bounding coordinates of the square area covered by the file, just keep the minimal and maximal values of each bounding coordinates.

	\|}		\|}

2014-08-28T00:32:44Z

Annexe A

← Older revision		Revision as of 19:32, 27 August 2014
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	= Annexe A =		= Annexe A =
	~~Getting~~ the bounding coordinates from a DWORD value:		== Computing the bounding coordinates from a DWORD value ==

	<pre>		<pre>

2014-08-28T00:31:35Z

Sections

← Older revision		Revision as of 19:31, 27 August 2014
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	== Sections ==		== Sections ==
	Following the header, at offset 0x38, there are as many sections as defined at offset 0x14 of the header. Each section has a size of 20 bytes and has the following structure:<br/>		Following the header, at offset 0x38, there are as many sections as defined at offset 0x14 of the header. A same file may contain sections of different type. Each section has a size of 20 bytes and has the following structure:<br/>
	{\| class="wikitable"		{\| class="wikitable"
	\|-		\|-

2014-08-28T00:30:47Z

Sections

← Older revision		Revision as of 19:30, 27 August 2014
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	\| 0x00		\| 0x00
	\| 4 - DWORD		\| 4 - DWORD
	\| Section type: one of the following values:<br/>		\| Section type (as defined by Microsoft Flight Simulator): one of the following values:<br/>
	* None = 0x0		* None = 0x0
	* Copyright = 0x1		* Copyright = 0x1

2014-08-28T00:29:01Z

BGL Common Format

← Older revision		Revision as of 19:29, 27 August 2014
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	= BGL Common Format =		= BGL Common Format =
	All BGL files share the same generic format. A BGL file is made of a header, sections, subsections and subsection data. Subsections are children of sections. The sections are here to help us locate the subsections in the file. Data specific information is contained in the subsections data and their format is dependent on the section type.		All BGL files share the same generic format. A BGL file is made of a header, sections, subsections and subsection data. Subsections are children of sections. The sections are here to help us locate the subsections in the file. Data specific information is contained in the subsections data and their format is dependent on the section type.
	<br/>A BGL file always start with a header (Size = 0x38 bytes), followed by a list of section pointers. The number of section pointers is defined in the header.		<br/>A BGL file is really a big container where all kind of information can be stored (in the subsection).The meaning of the data contained in the subsections is known only by the application using it. Th only contraint is for the file to comply to the generic format described below.
			<br/><br/>A BGL file always start with a header (Size = 0x38 bytes), followed by a list of section pointers. The number of section pointers is defined in the header.
	<br/>		<br/>
	[[File:Cvx_BGLFormat.png]]		[[File:Cvx_BGLFormat.png]]

2014-08-17T23:41:03Z

Segment Structure

← Older revision		Revision as of 18:41, 17 August 2014
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	== Segment Structure ==		== Segment Structure ==
	Then for each segment (the number of segments is defined at relative offset 0x00 of the entity structure (see Entity Structure above), we have the following structure:		Then for each segment (the number of segments is defined at relative offset 0x00 of the entity structure (see [[#Entity Structure\|Entity Structure]] above), we have the following structure:
	{\| class="wikitable"		{\| class="wikitable"
	\|-		\|-

← Older revision		Revision as of 15:45, 1 September 2014
Line 1:		Line 1:
	~~{{Infobox-Applicable-FSVersion~~
	~~\| P3D2 = true~~
	~~\| P3D = true~~
	~~\| FSXI = false~~
	~~\| FSXA = true~~
	~~\| FSX = true~~
	~~\| FS2004 = unknown~~
	~~\| FS2002 = unknown~~
	~~\| FS2000 = unknown~~
	~~\| FS98 = unknown~~
	~~\| XP10 = false~~
	~~\| XP9 = false~~
	}}
	= Introduction =		= Introduction =
	cvx*.bgl files can be read by the TmfViewer.exe application provided with the FS SDK. They contain TERRAIN_VECTOR_DB sections. These sections and subsections describe the different layers (roads, railways, water polygons, etc.) along with the geographical coordinates.		cvx*.bgl files can be read by the TmfViewer.exe application provided with the FS SDK. They contain TERRAIN_VECTOR_DB sections. These sections and subsections describe the different layers (roads, railways, water polygons, etc.) along with the geographical coordinates.