Worklog for Foppy
Grand Prix
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The game is finished! It took some time, mainly because I didn't do
anything, for a while. But the last couple of days I have been busy with
the finishing touches, such as a starting light sequence, title screen,
game over screen, and readme file. The goal in the final game is to win the gold cup by completing 8 laps (or more). Bronze and silver cups can be won for 6 and 7 laps respectively. I admit, it is a difficult game, in fact I myself have only won the gold cup one or two times. But of course, this is a proper formula one simulation, and as such it should be difficult, as is the real thing. ;) Grand Prix can be downloaded from my website: Foppygames Homepage. Or use this direct link: grandprix.zip (4.6 MB) --------------- Foppygames |
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| A tunnel effect has been added. This consists of the following steps: - certain road segments are marked as being part of the tunnel - as the first tunnel segment comes into view, an entity for the start of the tunnel is created on the horizon (colored white, see first picture) - every N distance units the tunnel comes closer, an extra tunnel entity is created (colored black); this creates the tunnel walls inside the tunnel - in the tunnel, grass is colored black, to fill in holes in the 'wall', - and the track is drawn in a darker shade than normal using something like SetColor(100,100,100) instead of SetColor(255,255,255) The above is not a complete and perfect explanation, but it comes down to using trickery such as black grass to create the illusion of the black inner tunnel walls. Inside the tunnel, the upper part of the screen (where normally the horizon is visible) should also be black, this is also taken care of by the tunnel entities, which cover the top part of the screen when the 'camera' is in the tunnel (as in the second picture). This tunnel has been strategically placed on a level stretch of road, to avoid having to deal with drawing the roof of the tunnel in case of the tunnel going up a hill. Problems here would be the color of the roof, as well as the smooth outer edge. It would perhaps involve drawing an elevated 'copy' of the road, using textures for the roof of the tunnel. This system could then also be used for the default case where you see the roof from the inside of the tunnel. However I want to finish the game soon so I am sticking to the current system. Edit: In fact, a smooth edge would not be a problem, as in the current implementation the tunnel is full-width, it covers the whole screen. So there is no edge to be drawn. However, going up a hill, it would probably look strange to still have the tunnel full-width. People would start to wonder why a tunnel is there, if nothing is on top of the tunnel but an empty roof. They would send me e-mails about it and I would be forced to build a complete city or mountain on top of the tunnel, delaying the project by years! A small addition that may be feasible is to have lights or something like that in the roof and/or walls of the tunnel, to get some more things moving towards the camera and increase the 3d/speed effect.   --------------- Foppygames |
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| I have received kind permission from coda (coda.s3m.us)
to use two of his songs. I have used some of his music before in my
games Manotrooper and Ranger and like it a lot. One song plays on the
title sceen, the other plays in a loop during gameplay. I used
Foobar2000 (www.foobar2000.org) to convert from MP3 to OGG for use in Blitz Max. The hills have been improved upon and now I am happy with them. Previously, I would move the horizon up and down based on the height of the road on the horizon. Now, it slowly scrolls up or down based on the slope the player is on. This is more like the effect I pointed out in my previous post (Coaster Racer). I have added pools of oil that appear on the track when a car explodes. In the near future cars will start sliding when driving through them. I ran into a problem with the oil, as they have to be flat on the track, but they would stick out (upright) when on a hill. A 3d effect was missing. So I have made it so that based on the slope of the road segment the oil is on, the sprite is scaled vertically (made shorter or taller) to match the perspective of the road. Also added: 'golden' cars that blink yellow and white and have high top speed. These will give extra points when overtaken. --------------- Foppygames |
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| Added: - skidding + smoke/dust effect when going through corner at high speed - lap counting now works - occasional exhaust flash + sound Last time I wrote I considered not adding a score, and to have a game structure in which you have to finish a number of laps, at a selected difficulty level. I have changed my mind, so the new idea is: - keep track of score (plus this session's high-score, maybe save to disk?) - endless game: it just gets more and more difficult - no difficulty selection I am not completely happy yet with the hill effect. I am now thinking about changing the way the background moves up or down when driving on hills. In some games you see the background move up or down slowly, with convincing results as seen in this example, Coaster Racer: https://www.youtube.com/watch?v=meHKtABu14U Of course in that game the effect is extra strong because there is no ground graphic left and right of the track. I want to try a few things to see if I can improve the hill effect in my game. Todo: - music (done) - experiment with hills (done) - endless game, difficulty increases per lap - keep track of score and session hi-score - some more smoke/damage/collision effects --------------- Foppygames |
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| This game is taking some time, because I work slowly. To speed things up, I have decided on the following game structure: - player has to complete 10 rounds - round timer starts countdown at 75 seconds - for every completed lap, 50 seconds is added - timer reaches zero: game over! - crashing your car is not game over, but costs time This is in fact similar to Pole Position, except that I do not add the qualification round, but instead have the player start at the same position, or maybe at a reasonable random position. Another difference is that I am considering not adding a "score" counter. You either finish the game or you don't. I can make a total of three circuits, to be used as three difficulty levels: easy, medium, hard. The levels would use different settings for: number of computer cars on screen, speed of computer cars, number of laps to complete, and time limit. It should be not too difficult for a beginning player to complete the easy level, maybe after one or two tries, and it should be a real challenge, even for someone who played many times, to complete the hard setting. --------------- Foppygames |
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| Added: - banners - signs - collisions can destroy car - starting grid The game has been reordered to use a central type "TGameMode". This controls the flow of the game, and in each state of the game takes care of updating and drawing relevant objects. Adding states made it easier to add a starting grid, were cars are already visible on screen but not yet being updated, so they don't move. When a timer reaches zero, the game switches to the next state, in which cars are updated, so they start to move. I think I will add a qualification lap, as in Pole Position, to determine the player's position on the starting grid. Probably still to be added: - qualification lap (cancelled) - race structure (how many laps, scoring, timing, etc.) (endless + more difficult per lap + scoring) - maybe more than one circuit? (cancelled) - selection of difficulty level? (cancelled) - online high scores? (cancelled) - explosions (done) - music (done) - full-screen display on different aspect ratios (done) - title screen (done) - game over screen (done)   --------------- Foppygames |
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| After Wiebo suggested it on youtube I have added hills to my game. I used the technique that was described by Lou Gorenfeld on http://www.extentofthejam.com/pseudo/
called "Faked Hills". It approaches hills in the same manner corners
are done. As the horizontal lines that make up the road are drawn,
starting a the bottom of the screen, a certain "DY" value is added at
each step to determine what will be the "Y" for the next line. Normally,
DY is one, which results in a flat road (watched from an angle) towards
the horizon. Using lower or higher values for DY (but the same value
for every step) will make the road look like it's going down or up. If
DY is increased or decreased with every step (for example using an extra
variable "DDY"), the road will curve up or down. It took me some time to implement this idea. I ran into a problem with the game objects and their drawing order. Previously, since the road was flat, I could first draw the road, and then draw all objects. The objects would appear on top of the road. Now, after adding hills, this drawing order was too simple, because you could see cars that were supposed to be hidden by a hill. Cars and hills had to be drawn in the correct order. It also meant that the road had to be drawn from back to front, so hills would actually hide objects (and road segments) by being drawn on top of them. However, the details of the road are typically computed from the bottom of the screen up to the horizon. So I had to first compute all details of each line of the road in the normal bottom to top fashion, store those in an array, and then later use that array to draw the road from back to front. In the same loop that draws the road lines, game objects are also drawn, whenever the Z value of the current piece of track corresponds to a game object's Z value. I then added a bit of code to draw the front wheels of the car higher or lower according to the current "slope". This went a bit crazy as cars in the distance that were going up a steep slope would have their front wheels 10 meters up in the air. This was a reminder of how "pseudo 3d" it all is... some numbers used to represent angles or heights do not really make sense, you just have to apply them and maybe multiply with another magic number to get a nice result. The current slope is also used to increase a car's acceleration, if the road is going downwards. In order for the hills to look more convincing you also have to move the horizon into the opposite direction. For this to be possible you need background graphics that cover a larger vertical space than would otherwise be necessary. So I took the "front" horizon image (there are three) and made it higher. I used the tree images I had used before to fill up the extra space. Somewhere along the way I lost the clouds. I think they will be added again, but they have to be separate entities from all other objects, because they act quite differently. Either that, or I could just draw some clouds on the horizon images. --------------- Foppygames |
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| Added: - car shadows - bushes - new horizon - clouds - more dynamic car graphics The horizon is made up of 3 images: trees, hills, and distant hills. These are scrolled at slightly different speeds to give a small parallax scrolling effect. The cars are drawn using the Rect() command (except for the tires, which are bitmaps). I have applied a bit of rotation now when the car is steering. This makes the cars more dynamic and a bit more 3d-ish. A new video: --------------- Foppygames |
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| I haven't yet described what the game is about, apart from it being a racing game. The player will be placed on the starting grid, together with a few CPU cars. There will be a typical "START" banner. The race begins (maybe there's a start sequence with lights and sounds) and everybody starts driving. There's a "SCORE" counter, this keeps track of how many cars the player has passed. (If a CPU car passes the player, the score is decreased.) There's also a "LAP" indicator. (Counting laps done, or indicating the current lap number, or counting laps remaining, there are several approaches to this counter.) The goal of the game will be for the player to pass as many opponents as possible in a set number of laps. There is no group of 10 or 20 cars like in real life, new opponents just appear on the horizon as the player car drives on. CPU cars that move off the bottom of the screen (or off the top of the screen) are removed from memory. An extra margin is used at the bottom of the screen so that CPU cars can actually return into view, overtaking the player, if the player slows down for some reason. Actually, I think there should also be a system to introduce cars at the bottom of the screen. Collisions with other cars, signs and trees (if any) will probably mean "GAME OVER" if the objects hit each other at high speed. Low-impact collisions will slow the player down. --------------- Foppygames |
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| Added: - collision detection - AI cars avoiding objects - better looking tires It took me a while to add a next step, which happened to be collision detection. This is working now. It simply checks, for each car, whether that car moves into an entity (which includes other cars and signs). Cars can only collide with things that are in front of them and which they are closing in on (this way, instant double collisions between the same objects are avoided). Part of the collision check is the 'length' of the car. It occurred to me that the same function could be used by the AI cars to avoid objects, by using a length that is, for example, 20 times the normal value. If the function returns true, there's an object within 20 car lengths ahead. The AI car then selects a different lane to drive in. In doing so it does not check if a car happens to be in that other lane. (I don't want to make things too complicated.) The cars are drawn using rectangles. An exception on this rule has been made by using images for the tires. They now have rounded corners and a simple shading effect. By changing the SetColor values rapidly, a flashing effect that represents the turning of the wheels is achieved. --------------- Foppygames |
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In 2003 I tried writing a pseudo 3d racer in Blitz 3D, but couldn't get
the corners to look convincing. Now I am trying again but in Blitz Max.
I found a nice overview of such games and a description of the
techniques involved, here: http://www.gorenfeld.net/lou/pseudo/ Using Lou's Pseudo 3d Page as a reference I started programming, and I am happy about the results so far. Below is a video. The cars are drawn using rectangles. The computer controlled cars actually use the same steering logic as used by the player car: they accelerate and brake to reach a recommended speed for the road segment they're on, and then apply steering to stay on the track. Once cars can collide I will have to add code for the AI cars to avoid other cars... --------------- Foppygames |