PeteE Posted January 28, 2020 Share Posted January 28, 2020 (edited) Here is a TI99/4A port of the arcade game "Bump 'n' Jump" from Data East in 1982. It is written in assembly language, developed using Ralph's XDT99 tools. It runs on a bare console and does NOT require 32K expansion. It features full-screen vertical scrolling at pixel resolution in bitmap graphics mode. Use joystick 1 or the E S D X keys to accelerate/steer/decelerate, and Fire, Space bar or Enter to jump. The P key can be used to pause and resume play. Colliding cars will temporarily bounce in opposite directions, and bounced opponent cars may smash against the barriers. Various cars have different point score values. Your car speed must be at least 100 to be able to jump. Jump over gaps in the road, or to avoid being bounced into a hazard. Upon landing, cars underneath will be instantly smashed. Completing a road will score bonus points for the number of cars smashed, before moving on to the next season. An extra life is awarded every 30K points. Landing on an island awards 1000 points. This game was started when I had an idea for a method of scrolling the whole screen, and I made a prototype for the 4K contest in early 2018. The prototype proved the scrolling effect worked, and then I spent a lot of time compressing it down to fit in 4K. The prototype used only 13 out of the 16 track segments, used only one season's color table, and had track data only for the first two levels, (before going off into the weeds and filling video memory with garbage.) The full game has 8 levels of 64-segment road, with more complicated segment transitions that didn't work within the prototype transition scheme. Instead of loading a new transition set every 32 rows (1 segment), I needed to allow reloading every 8 rows (1/4 segment). This is fine because the bitmap graphics mode is 3 chunks of 8 rows, so each chunk can be updated individually. Some of the original segment elements had to be adjusted to made the seams easier to fit into the transition table. The transition tables are limited to 32 entries, since each transition consumes 8 of the 256 characters. I spent some of my last winter holiday vacation working on the transition table generation, and finally got it working. For this version I didn't bother with any compression: bank 0 is mostly program, bank 1 is track data, bank 2 is sprite data, and bank 3 is sound lists. The music was converted from the notes in a midi file that I found. Music plays on the tone channels 1 and 2, and sound effects play on tone 3 and noise channels. I grew up playing the Intellivision port as a kid, and have incorporated some of the same design elements into this version. The "Get Ready Player" and "Congratulations" screens have white text over a black background. Another similarity is that the opponent vehicle sprites are limited to a single color. This game is more-or-less complete. I considered adding a two player mode, but have run out of space in bank 0. bnp_8.bin bnp.rpk bnp_ea5.dsk Edited March 4, 2020 by PeteE 24 5 Quote Link to comment Share on other sites More sharing options...
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