Streams added 20.3.28
"Path" added 20.3.28
A very small part of the map
Part of the corresponding scene
by Graham Relf
A route actually taken on the short easy course
Buildings added 18.10.24
Non-orienteers can fall down into the mines
Version 19.4.1: this object moves itself around
19.7.24: Teleportation is back!
(If you can find it, as an explorer.)
In reverse order of version numbers, so the most recent changes come first.
Version numbers are dates of uploading (yy.mm.dd).
- 21.1.8: Engineers can now build roads across water (crude bridges) and save them to appear the next
time the program is run.
- 21.1.4: There is a new role: Engineer. In this role clicking on the map causes a menu to appear
for building a road from or to the clicked point. Roads are only visible to explorers and
engineers; they cannot be used to make routes easier for orienteers. Roads are not saved to appear
the next time you run the program (yet). Although roads can be drawn across water on the map those
sections will not be visible in the scene because there are no bridges (yet). Some objects could move
around for explorers but they will remain stationary for engineers. Also engineers will not fall down
- 20.9.4: The 45° bias in the routes taken by streams has been removed. This has changed the
routes taken by streams but they are still only experimental.
- 20.4.19: The "Max. detail" switch has been removed because switching it off made little difference
to performance. Map display code has been simplified and it now works correctly for streams when the
map is turned.
- 20.3.29: Green on the map made darker, to contrast with streams.
- 20.3.28: There are two new kinds of features in the terrain. They are both experimental, so users may
choose whether to switch them on, by ticking boxes in the settings area.
- Streams flow down from some water holes (ponds). Some end in lakes, others in marshy areas.
These streams often help with contour interpretation: is a contour uphill or downhill from its
The representation in the scene view is very basic and will need improving; it does not yet indicate
when you are standing in a marsh.
The previous Water (key w) button, to make a stream from the observer's position, has been removed.
NB: Turning the map through 90° does not work properly for streams but orienting the map is fine.
- Paths are shown on the map as grey lines of varying width, sometimes with blobby areas. In the
scene they appear as rather badly placed paving. It is problematic to see how they could be represented
by conventional dashed lines on the map.
- 20.3.12: Buildings have a greater range of heights and may be multistoreyed. Helicopters rise
automatically if necessary to fly over buildings and will not descend below 30m above towns.
- 20.2.16: An experimental version of part of The Forest using three.js and WebGL may be seen
- 20.1.30: Two small changes for orienteers: (1) the control card now says "DONE" in the right
column when a control has been visited instead of "punched", (2) the start and finish of the
easy short course have been moved slightly to be in open areas.
- 20.1.25: Bug fixed in which approaching a building too close resulted in a confusing display of walls
(and it was possible to get through buildings without seeing the inside! Quantum tunnelling?)
For explorers, wall drawing in mines has been improved. An auto-running explorer can no longer fall down
- 20.1.20: For orienteers: there is no longer a button to show the control card because it is always
shown for you. The stop button is now larger and shown to the right of the main display.
- 20.1.14: Hovering over the new buttons now shows alternative key-presses that may be used. In particular
in the scene, 'f' can be used to go forward or 'b' to turn back and these keys avoid the browser screen
scrolling which could sometimes happen with the up and down arrow keys. Using the 'f' key like this means that
the special key for moving forward repeatedly has changed to 'a' for automatic.
Explorers will see extra buttons on the right that may be useful to those without keyboards.
- 20.1.2: Major redesign of the user interface aiming at easier use on devices without keyboard
(tablets, phones). Some user interface components now move around depending on how much screen area is available.
- 19.8.5: A further (4th) stage in the treasure hunt is now available.
- 19.8.1: Orienteers can now display graphs from the results table showing the height profile of the exact
route they took.
- 19.7.24: Explorers will find a further step in the treasure hunt, involving a monolith and a red box.
- 19.7.22: For orienteers: (a) there is a new course to select, short but less easy; (b) when a control is
correctly visited 3 bleeps will sound.
- 19.7.14: Fixed bug which could arise when entering a building. Drained lakes do not have vegetation.
- 19.7.7: For explorers: there is equipment inside buildings to enable a further stage in the treasure hunt.
- 19.6.19: A useful measuring device can be found underground. It helps to get into things.
- 19.6.11: For explorers: the scene display in the underground mines has been completely redesigned. It now
uses the same techniques as above ground (in the wood or inside buildings). Instead of blindly plunging
16 metres at a time through black tunnels there is now an open view of the mined areas, lit by ceiling lamps.
This enables free movement with a stride length as set by the drop-down on the HTML page (from 1 to 5 metres).
This will make it possible for more things to happen underground - yet to come.
- 19.5.26: There are now 8 varieties of mature tree instead of 4.
2 more optional parameters added to the URL: r (range) and s (stride) both of which take numerical values
in metres which should match those available in the drop-downs. Eg:
- 19.5.1: For orienteers: if the browser window is wide enough the control card stays visible alongside
the scene or map rather than popping up briefly only on request.
- 19.4.22: It is now possible for an orienteer to stop a course part way round but still see the analysis
and route taken up to that point.
- 19.4.16: Bug fixed in which using check boxes while inside a building caused brief view of external scene.
- 19.4.10: Map scroll and kind are now selected from drop-down lists.
Scenes with longer range selected should now draw faster.
- 19.4.6: Fixed bug which was preventing entry to doors on buildings (since 19.3.15).
- 19.4.1: Two moving objects. When they meet they transform into something particularly appropriate
for this terrain and the way it is drawn on tiles, as described by Lewis Carroll in 1871.
- 19.3.29: First autonomously moving object added. It may be seen on the track by explorers.
- 19.3.15: Track added to legend box. Internal improvements.
- 19.2.24: Bearing drift no longer occurs if standing on a paved area (town or track).
Every mine shaft now has an escape ladder (previous restriction removed).
- 19.2.21: Helicopters now stay where you land them rather than flying back to their starting position. They
can be reused from where they landed.
- 19.2.20: Tracks and streams (key w) are now shown correctly when the map is turned in steps of 90°
- 19.2.19: There are some tracks in the starting part of the map, linking some built-up
areas. They are shown as dashed black lines on the map and it is amusing to follow them both on the ground
and from a helicopter. Only those in the explorer role will see the tracks.
Orienting the map works but turning through 90° does not. Now that we have map orienting, I am thinking
about removing the 90° map turns anyway.
I have done statistical timing tests and the tracks do not significantly slow down map or scene drawing.
For programmers: this demonstrates that objects can be positioned on the ground (using an object, ie very
efficient hash table, in terrain.js) but goes against the automatic terrain generation principle. But then,
tracks in the real world have to be made by people (or animals)!
- 19.1.15: If using a fast enough machine it is now possible to start The Forest with the effects switched on
that are normally done by the check boxes at the bottom of the page. This can be done by adding up to 4
parameters to the URL (in any order):
You are unlikely to start with rain but the others may be useful. Each parameter that is present must have
the value y to switch the relevant effect on.
- 19.1.14: Explorers can find some encrypted hints where others would see traffic cones. New challenge: crack the code!
- 19.1.9: Link to map-reading quiz. Other internal improvements users should not notice.
- 18.12.30: Buildings now have windows (externally). Bug fixed in which doors could sometimes disappear.
- 18.12.27: Visible range is now indicated on the map by a dashed red circle (explorers only).
- 18.12.23: Map display is protected against disruption by keys held down and repeating.
The list of ranges available has been modified and the furthest is now 400m (for fast machines).
Explorers only: on entering a helicopter it immediately rises 10m.
- 18.12.20: It is now possible to orient the map, so the direction you are facing is straight upwards.
A new check-box enables this effect to be switched on or off. 90° turns are not allowed while it is on.
(I am surprised how little it slows down map display - a reason I had put off doing this.)
- 18.12.18: Inaccuracies in drawing buildings have been fixed by drawing them quite differently (in sections).
Vertical scale increased again by 10%.
- 18.12.14: Start & finish banners improved and they now say which is which. New grass and moor images.
- 18.12.13: Fog starts at 75% of the horizon distance instead of 50%.
Anyone addressing the site with a non-https URL will now automatically see it as https.
- 18.12.11: Foggy horizon now also applied to orienteering markers and start/finish banners.
- 18.12.10: Explorers may find helicopters on open ground. It is possible to board and ascend to get aerial
views of the terrain. This gives another way of studying the relationship between map contours and the ground
relief. Forward motion and altitude changes are always in steps of 10m. When the helicopter is brought back to
ground level it disappears, having flown back to its base.
- 18.12.8: Tidied ground tiles.
- 18.12.2: Independent check-boxes to control effects: detail level, fog and rain.
For programmers: how the fogging is done is described in detail
- 18.11.30: Now everything can be hazy at the horizon but only if max detail box is ticked.
- 18.11.27: Experimenting with making the horizon hazy so that objects do not appear too suddenly. So far
only buildings and paving are affected and the result is better for horizon ranges greater than 60m.
The j key does not work on paved areas (towns); a message is shown.
- 18.11.16: The status line for scene drawing now shows how many images were drawn to make the scene
(the number of calls to the drawImage method of the 2D context).
30 kilobytes, to 148kb and makes the initial start slightly slower. Previously scripts for mines and building
interiors were only loaded when needed but that could cause problems if the user was no longer connected to
- 18.11.9: There are now things to see inside buildings, including some potentially useful information.
- 18.11.7: (For non-orienteers.) The treasure chest now has a note in it which tells how to proceed
to a further stage, using an interesting feature I discovered on the map near Treasure Island.
Doors on all buildings can now be entered if you know their key codes (something for you to work out).
Buildings all have interiors to view. Leaving again through the door does not require a code.
For those without keyboards: tapping or clicking near the centre of the scene is equivalent to
the Enter key.
- 18.10.30: The vertical scale for drawing scenes has been increased by 20% which makes contour
effects more visible. This is possible now that users can scroll the scene up or down.
Every building has a 2m wide door on one of its sides, painted in a colour of its own.
These doors do not do anything yet.
The maximum-detail check box is now switched off whenever the page is refreshed
(previously its state did not change, confusingly). When the box is checked a new consequence is that
flat roofs are drawn on any buildings which the observer is looking down on.
- 18.10.25: When viewing the scene it is now possible to look up or down (+ or - keys or click buttons).
- 18.10.24: Towns now have solid buildings, if rather plain. They are each shown on the map and it is necessary
to navigate along the paved streets, avoiding the walls. Slightly ragged display and plain walls will be worked on
further in due course.
- 18.10.19: Some speed improvement in scene drawing. New check box for max. detail (avoids distant trees looking like a row of teeth on a comb).
- 18.10.18: This new "What's new" page. Links changed from http to https
- 18.10.16: New leafier tree type
- 18.9.1: Site made https, so browsers stop saying it is risky (it does not collect any data!)
- 18.8.15: Detailed route can be plotted at end of orienteering course
- 18.8.6: New role: expert orienteer sees simpler forest, harder to navigate
- 18.8.3: Users can exchange new courses in course planner role via a course management page
- 18.7.30: Orienteers can now choose a score event
- 18.7.20: Explorers only: treasure chest no longer disappears after it is first seen
- 18.7.14: V symbols (mines & ponds) turn with the map. Map no longer recentres as orienteers move.
- 18.7.3: Fix for arrow keys which were not recognised in some browsers
- 18.6.26: There is a green door in a wall for explorers to enter and see a different view. There is a way back!
Orienteers will not encounter the door, nor be distracted by other things aimed at explorers.
- 18.6.3: Experimental weather: explorers can see the effects of rain
- 18.5.22: Animate climbing ladder out of mines
- 18.5.20: Fixed bug in which nearest trees were scaled wrongly
- 18.5.18: Clearer forward motion in mines
- 18.5.17: Messages shown over image, not using alerts. URL myforest.uk shown in scene
- 18.5.15: Treasure hunt available for explorers. New URL myforest.uk
- 18.5.7: Explorers can fall into mineshafts (restoring some code removed in 18.2.20)
- 18.5.6: Depressions changed to rootstocks because graphics for depressions too difficult
- 18.4.20: Orienteers will see markers on a quarter of features not on their course
- 18.4.19: Bug fixed: blank screen due to position loss after slow turn by 360 degrees
- 18.4.18: Smoother contours, every 5th one thicker
- 18.4.15: Scarecrow added
- 18.4.10: Stride can be changed by user
- 18.4.7: Clearings tiled before mines - much better
- 18.4.5: Trees no longer in straight rows
- 18.3.31: Crude images for mines and ponds. New secret keys - see User Guide
- 18.3.26: Friendlier for smartphones (click near edges of image, bigger buttons)
- 18.3.21: Contour problem solved
- 18.3.17: Map can be turned. Visible range in scene adjustable to suit processor speed
- 18.3.13: Program structure improved
- 18.3.9: Textured ground. All point features displayed but rather crude
- 18.3.8: Trees and buildings now visible in the perspective view
- 18.3.7: Scene drawn in true perspective. Ground and boulders, other features to be added
- 18.2.28: Planner really can create new courses, persistent in most browsers
- 18.2.26: Changes in course.js to enable planners to create new courses
New sine and cosine arrays in observer.js to reduce recalculations
Bearing drifts randomly by up to 3 degrees on each step forward
- 18.2.24: Novice role shows position on map (can now compare novice/experienced on 1 course)
- 18.2.23: Start and finish banners
- 18.2.22: Route analysis table displayed when a course is completed
- 18.2.20: Improved clock. Selectable courses (2 so far). Steepness ahead affects speed
All reference to teleporters and cave interiors removed
- 18.2.18: Clock. Control card is punched when within 5m of correct control. Finish works
- 18.2.17: Roles take effect. 1 short course available. No card to punch yet
- 18.2.16: Role can be selected but does not do much yet
- 18.2.14: O-markers drawn at all point features (this is temporary, for testing)
- 18.2.13: New 3D plot
- 18.2.10: Several boulder images
- 18.2.9: Point features indicated by text in the scene ahead
- 18.2.8: Some standard map symbols for orienteering point features (no more red boxes)
- 18.2.7: Colours changed to ISOM2017 standard for O-maps. North lines added
- 18.2.6: terrain.js interpolates height for smoother contours
- 14.7.1: Animating down into caves
- 14.6.25: Cave entrances
- 14.6.24: Teleporters
- 14.5.14: First graphics, modularise
- 14.5.12: More object-oriented
- 1986: "Explorer" version for ZX Spectrum, with graphics by Simon Dunstan of RamJam Corporation,
published by Electric Dreams.
- 1985: Version for BBC Microcomputer made by Cunning Running Software
- 1983: Sinclair ZX Spectrum version published by Phipps Associates
- 1982: Original program "The Forest" in Basic & Z80 assembler for TRS-80 published by Molimerx
Further enhancements being considered
- The ground cover is still untidy. It is a compromise to avoid
slowing scene drawing too much. I am still thinking about ways to improve this.
- Add profile graphs to the results analysis for orienteers: compare crow-fly
profile with that of the route actually taken. Give some statistics of height gain
and loss (energy efficiency).
- The treasure hunt will continue to have further stages.
- Map movement could be speeded up by sliding the part that remains visible and only
drawing from scratch the newly revealed part.
- More varied content inside buildings.