Decided to blog my progress in creating a game for the Atari 2600.
This thread launched this project: http://www.atariage....new-dk-for-vcs/
Asked for a new DK for the VCS, I had done some mock-up screens with the latest batari Basic and posted them.
The game, now called DK Arcade 2600, has all 4 levels, with the adding of Level 3 elevator screen.
Might release a playable demo soon!
Byte Knight starts coding game logic with my art and sounds, basically starting fresh.
In two weeks Level 4 has exceeded what I had coded by miles.
Working score, hammers, climbing fireballs are all working.
Most recent binary: Jumpman1234_20130217.bas.bin (32KB)
Blog name changed to: "DkbBDPC+ 2600 Jumpman" to be more obscure.
My idea of PUSHing playfield data to the screen along with routines from bogax and SeaGtGruff have resulted in the opening "horizontal girders to sloping girders" not going over cycle, and therefore rock steady on real CRT televisions! Thanks everyone!
Also work done in compressing data has resulted in compression of the data for the Rivet Level 4. Big ROM savings!
Kong sprite changed to frowning, then the toothy grin with three "growls" made from only changing audio volume - (I have always wanted to use that effect.)
The "How High" screen now has custom score to show 25m 50m etc. (probably only ever one monkey though). Also now drops into the game after the How High tune (before it looped until fire button).
Unsuccessful in attempts to flicker playfields in more than one level (runs out of ROM). Ideally Level 1 would have red girders and blue ladders like Level 3 (the elevators). Four playfields do fit, but then there is no room for sprites and color data.
Sorry, no binary as Level 1 needs reverted due to unsuccessful attempts at "Playfield Flipping."
Latest binary is Level 4 (Rivet Level) found in this post (with source code): http://atariage.com/...rn-help-needed/
Latest progress: 01-24-2013
Nobody thought to mention the rivet screen girders were off? (I didn't realize either!)
.I will probably go with this titlescreen, it uses less ROM.
. Started putting all levels in one ROM
. Changed 1st level to one Playfield (all red, no flicker) so all 4 levels can fit.
. Lots of bugs and sloppy code. Levels 1, 2 & 3 in ROM.
. No gameplay logic programmed yet. Get to top to see next bank http://www.atariage..../icon_smile.gif
. On real hardware Level 2 bank crashes back into Start ?? On emulation you can move to the top to see Level 3.
. Note: Making anything playable is indeed a challenge. Ideas can make you run out of bytes very fast!
. Note: If I can get this far in batari Basic, in full assembly with an EEPROM chip like Chetiry uses, there would be space for many original levels and music. It remains to be seen how far I can get with run, jump and climb with the space remaining in Basic (and then there are bonus items and hammers I haven't even begun to think about)
. Fixed girder graphics level end of 1, 2, 3, 4, 5, & end of 6 - they were inverted
. Saved hundreds of bytes graphic data by-
defining only one Player0 colors for many Jumpman animations
Using only 2 values for the 2 playfields' color instead of repeating the same color value for each line (358 bytes)
. Lady appears when at top of level 6
. Ladder detection started (proof it will work), can only climb when at ladder
X Sprite incorrect when ladder detected, but not climbing
X Ony jumps when moving or facing right, jump left broken
. Made a barrel sprite roll down the girders from top left to bottom left.
. Princess version 2.0
. Artwork for blue girder level.
.Level 2 - Pie?
downloads: 88 - OLD
new: JumpmanOra20121109.bas.bin (32KB)
Another pretty picture coded:
I was dreading doing the elevator screen. I was thinking it couldn't be done -- that it was too much and should maybe just be skipped.
Then I had an idea how to make the elevators work well.
The layout went very quickly.
The sprite copy lined up perfectly! I was amazed, after having to make a 1 color clock compromise on the pie level moving ladders.
More thouhghts below.
NEW: JumpmanELe20121108.bas.bin (32KB)
OLD: JumpmanELe20121108.bas.bin (32KB)
.Good news: Levels 2 & 4 ( orange and blue girders ) do not flicker the playfield. Levels 1 & 3 flicker.
Sprites 1-9 will always flicker when aligned horizontally.
.Four levels (6 playfields) will not fit in the graphics bank.
Playfield data can go in another bank, but using it is not so easy. Shouldn't I be able to pass a low / high pointer to this data instead of plotting pfpixel a whole playfield?
Melody board can be built with extra RAM / ROM to hold this data, but batari Basic will have to be changed to allow compiling into a larger graphics bank. Help!!!!
.Sound is already done for the TIA if you want to use that horrible noise from the 7800 version (groan)...