artrag Posted May 11, 2020 Share Posted May 11, 2020 3 hours ago, Asmusr said: All I can say is that at the moment I'm interested in developing this project further. But there's currently not much to make a game from, and I don't have any specific idea for a game. I think you first need sprites implemented. According to the frame rate achieved, you will be able to design a game idea that fits the constrains Quote Link to comment Share on other sites More sharing options...
jstimson Posted May 11, 2020 Share Posted May 11, 2020 Even just a variation on TOD would be cool. Maybe find a way to implement the "in room" battles in a 3D way? It could still be turn based, but just a switch-up on the visuals. Quote Link to comment Share on other sites More sharing options...
jrhodes Posted May 11, 2020 Share Posted May 11, 2020 "Hunt the wumpus 3D" Quote Link to comment Share on other sites More sharing options...
oddemann Posted May 12, 2020 Share Posted May 12, 2020 9 hours ago, jrhodes said: "Hunt the wumpus 3D" Yes, that is a great idea! But there are some challenges with "seeing" stuff. Or maybe signs? Could replace the overview? But a simple shoot em up is also a start! Slow speed and speeding it up. One bady and adding on badys for next level. Or a shoot em up that is a maze that you have to get to the end to get to the next maze. Dead ends and some of them has more amo, first aid kit and so on. Quote Link to comment Share on other sites More sharing options...
Asmusr Posted May 12, 2020 Author Share Posted May 12, 2020 17 hours ago, artrag said: I think you first need sprites implemented. According to the frame rate achieved, you will be able to design a game idea that fits the constrains Exactly. Without anything other than walls very little interaction is possible. But adding big zooming sprites using a limited number of character tiles is quite challenging. Quote Link to comment Share on other sites More sharing options...
Tursi Posted May 12, 2020 Share Posted May 12, 2020 "Everything is a block of tofu..." 1 Quote Link to comment Share on other sites More sharing options...
PeteE Posted May 13, 2020 Share Posted May 13, 2020 I was wondering to myself how a raycaster could work in 9918A multicolor 64x48 pixel mode, if it would even be possible with its unusual screen and pattern table layout. There would need to be a way to quickly render columns of pixels, but each character pattern contains two pixels side by side. Suppose we process two columns at once and combine the pixels into each byte written to the pattern table. If every other column data is pre-shifted by 4 bits, we could then bitwise-OR the two column bytes together, which should be pretty fast. The screen table is initialized with columns of 0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5 adding 6 to every byte when moving to the next column. Now to draw the screen, the pattern table can be written sequentially, each byte drawing two side-by side pixels, moving downward. I coded up a screen drawing function that runs from scratchpad RAM to see how fast it goes, and I get 83190 cycles (~28ms) per screen update. May I copy your raycasting code to test my multicolor screen drawing function? 1 Quote Link to comment Share on other sites More sharing options...
Asmusr Posted May 14, 2020 Author Share Posted May 14, 2020 9 hours ago, PeteE said: I was wondering to myself how a raycaster could work in 9918A multicolor 64x48 pixel mode, if it would even be possible with its unusual screen and pattern table layout. There would need to be a way to quickly render columns of pixels, but each character pattern contains two pixels side by side. Suppose we process two columns at once and combine the pixels into each byte written to the pattern table. If every other column data is pre-shifted by 4 bits, we could then bitwise-OR the two column bytes together, which should be pretty fast. The screen table is initialized with columns of 0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5 adding 6 to every byte when moving to the next column. Now to draw the screen, the pattern table can be written sequentially, each byte drawing two side-by side pixels, moving downward. I coded up a screen drawing function that runs from scratchpad RAM to see how fast it goes, and I get 83190 cycles (~28ms) per screen update. May I copy your raycasting code to test my multicolor screen drawing function? I did that myself (a multicolor renderer without a raycaster) a while back, and I am indeed considering if that's the way to go with this project. You're welcome to try your own renderer with my code, of course. 2 1 Quote Link to comment Share on other sites More sharing options...
Asmusr Posted May 14, 2020 Author Share Posted May 14, 2020 Here's the routine I used to draw two columns given top, height and color. Spoiler ******************************************************************************** * * Display two vertical multicolor strips * * R3: Strip 1 structure (top, height, color) * R4: Strip 2 structure (top, height, color) * R14: VDPWD * VDP write address must already be set up * * On return R3 and R4 are incremented by 6. * R0-R12 are modified. * STRIP MOV R11,*R15+ * Push return address onto the stack MOV *R3+,R5 * Get top 1 MOV *R4+,R6 * Get top 2 MOV *R3+,R7 * Get bottom 1 MOV *R4+,R8 * Get bottom 2 MOV *R3+,R9 * Get color 1 MOV *R4+,R10 * Get color 2 * Two sky pixels C R5,R6 * Compare top 1 and top 2 JGT STRIP1 MOV R5,R2 * Get number of sky rows to display from strip 1 JMP STRIP2 STRIP1 MOV R6,R2 * Get number of sky rows to display from strip 2 STRIP2 JEQ STRIP4 * Move on if zero MOVB @SKY,R1 * Get sky pixel colors STRIP3 BL @VDPCPY * One sky pixel, one strip pixel STRIP4 MOV R6,R2 * Get top 2 S R5,R2 * Top 2 - top 1 JEQ STRI19 * If zero this section can be skipped JLT STRIP5 * Jump if strip 1 starts after strip 2 MOV R9,R1 * Get color of strip 1 SLA R1,4 * Move to 1st nybble SOCB @SKY2,R1 * Combine with sky pixel colors MOV R6,R12 * Save top 2 as the start of next section JMP STRIP6 STRIP5 NEG R2 * Make counter positive MOV R10,R1 * Get color of strip 2 SOCB @SKY1,R1 * Combine with sky pixel colors MOV R5,R12 * Save top 1 as the start of next section STRIP6 BL @VDPCPY JMP STRIP7 STRI19 MOV R6,R12 * Save top 2 as the start of next section * Two strip pixels STRIP7 C R7,R8 * Compare bottom 1 and bottom 2 JGT STRIP8 MOV R7,R2 * Get bottom 1 S R12,R2 * Subtract end of previous section JEQ STRI17 * If zero this section can be skipped MOV R7,R12 * Save bottom 1 as the start of next section JMP STRIP9 STRIP8 MOV R8,R2 * Get bottom 2 S R12,R2 * Subtract end of previous section JEQ STRI17 * If zero this section can be skipped MOV R8,R12 * Save bottom 2 as the start of next section STRIP9 MOV R9,R1 * Get color of strip 1 SLA R1,4 * Move to 1st nybble SOC R10,R1 * Combine with color of strip 2 STRI10 BL @VDPCPY JMP STRI11 STRI17 MOV R7,R12 * Save bottom 1 as the start of next section * One floor pixel, one strip pixel STRI11 MOV R8,R2 * Get bottom 2 S R7,R2 * Subtract bottom 1 JEQ STRI18 * If zero this section can be skipped JLT STRI12 * Jump if strip 1 ends after strip 2 MOV R10,R1 * Get color of strip 2 SOCB @FLOOR1,R1 * Combine with sky pixel colors MOV R8,R12 * Save bottom 2 as the start of next section JMP STRI13 STRI12 NEG R2 * Make counter positive MOV R9,R1 * Get color of strip 1 SLA R1,4 * Move to 1st nybble SOCB @FLOOR2,R1 * Combine with sky pixel colors MOV R7,R12 * Save bottom1 as the start of next section STRI13 BL @VDPCPY JMP STRI14 STRI18 MOV R8,R12 * Save bottom 2 as the start of next section * Two floor pixels STRI14 LI R2,48 S R12,R2 JEQ STRI16 MOVB @FLOOR,R1 STRI15 BL @VDPCPY * Return STRI16 DECT R15 * Pop return address off the stack MOV *R15,R11 B *R11 SKY BYTE >77 SKY1 BYTE >70 SKY2 BYTE >07 FLOOR BYTE >EE FLOOR1 BYTE >E0 FLOOR2 BYTE >0E *// STRIP ********************************************************************* * * Fast VDP copy * * R1: Byte to copy (in MSB) * R2: Number of bytes to copy * R14: VDPWD address * VDPCP MOV R2,R0 SRL R0,3 * Number of groups of 8 JEQ VDPC2 VDPC1 MOVB R1,*R14 MOVB R1,*R14 MOVB R1,*R14 MOVB R1,*R14 MOVB R1,*R14 MOVB R1,*R14 MOVB R1,*R14 MOVB R1,*R14 DEC R0 JNE VDPC1 ANDI R2,>0007 * Isolate number of remaining bytes JEQ VDPC3 VDPC2 MOVB R1,*R14 DEC R2 JNE VDPC2 VDPC3 B *R11 VDPCPE *// VDPCP Quote Link to comment Share on other sites More sharing options...
LASooner Posted May 15, 2020 Share Posted May 15, 2020 Make a 3D version of A-MAZE-ING, then all you have to do is make cats that chase you. 1 Quote Link to comment Share on other sites More sharing options...
Elia Spallanzani fdt Posted May 15, 2020 Share Posted May 15, 2020 (edited) a simple playable demo in which at the beginning the maze is invisible (but the walls block you) and you can find buckets of of paint with which to color and make the walls appear. Edited May 15, 2020 by Elia Spallanzani fdt Correction 1 Quote Link to comment Share on other sites More sharing options...
Asmusr Posted May 16, 2020 Author Share Posted May 16, 2020 (edited) Here's the latest version. I don't have time to write about it now, but it's progressing really well. I fixed an issue with the height calculation which means that the walls are no longer rounded. Your challenge for today: find the two multi color striped areas. raycaster.rpk raycaster8.bin Edited May 16, 2020 by Asmusr 11 Quote Link to comment Share on other sites More sharing options...
Elia Spallanzani fdt Posted May 16, 2020 Share Posted May 16, 2020 Fantastic. Just one thing: the weapon shouldn't jump when you're stationary. Quote Link to comment Share on other sites More sharing options...
Asmusr Posted May 16, 2020 Author Share Posted May 16, 2020 5 minutes ago, Elia Spallanzani fdt said: Fantastic. Just one thing: the weapon shouldn't jump when you're stationary. I use the weapon to see the frame rate. 1 Quote Link to comment Share on other sites More sharing options...
speccery Posted May 16, 2020 Share Posted May 16, 2020 (edited) This really a cool project, thanks asmusr for working on this and congrats of making it work! Incidentally it also is a pretty much perfect test platform my new project, the StrangeCart cartridge for the TI-99/4A. This is something I wanted to try out for ages, but got around of implementing it only now. Here I have my TI-99/4A running your raycaster from the StrangeCart cartridge. 32k RAM expansion is provided by ET-PEB. The USB cables are used for debugging the cartridge and not needed to run. Edited May 16, 2020 by speccery 4 Quote Link to comment Share on other sites More sharing options...
jrhodes Posted May 16, 2020 Share Posted May 16, 2020 2 hours ago, Asmusr said: Here's the latest version. I don't have time to write about it now, but it's progressing really well. I fixed an issue with the height calculation which means that the walls are no longer rounded. The challenge for today: find the two multi color striped areas. raycaster.rpk 7.34 kB · 2 downloads raycaster8.bin 32 kB · 3 downloads Spear of DesTI99y 1 1 Quote Link to comment Share on other sites More sharing options...
Tursi Posted May 16, 2020 Share Posted May 16, 2020 4 hours ago, Asmusr said: Here's the latest version. I don't have time to write about it now, but it's progressing really well. I fixed an issue with the height calculation which means that the walls are no longer rounded. That's pretty great.. just a few years ago we still weren't sure this was even feasible, and there it is, better than we could have hoped! 7 Quote Link to comment Share on other sites More sharing options...
Asmusr Posted May 16, 2020 Author Share Posted May 16, 2020 It's interesting that this doesn't really require 32K RAM. As my code is now it does, but I think it could run almost as fine from a ROM cart. The only updated data in 32K are the positions of the enemies, and those could be moved to VDP RAM. 4 Quote Link to comment Share on other sites More sharing options...
Asmusr Posted May 29, 2020 Author Share Posted May 29, 2020 I'm experimenting with various things. One is the floor pattern, as you will see. You can also shoot the baddies now, but the baddies can't shoot you. Spoiler And for fun you can also shoot the walls. That means you can break out of the map. I'm displaying your current memory address at the top right corner. You can walk out of lower RAM and into DSR space at >4000. When you reach the cartridge area at >6000 you may experience "black ice" in the shape of immutable memory. Maybe you can find you way into the busy >8300 region, and travel on to the >A000 region and kill the evil program? raycaster.rpk raycaster8.bin raycaster.dsk 5 Quote Link to comment Share on other sites More sharing options...
sometimes99er Posted May 30, 2020 Share Posted May 30, 2020 Ha. And you can shoot the walls. Quote Link to comment Share on other sites More sharing options...
sometimes99er Posted May 30, 2020 Share Posted May 30, 2020 On 5/16/2020 at 7:29 PM, Elia Spallanzani fdt said: Fantastic. Just one thing: the weapon shouldn't jump when you're stationary. On 5/16/2020 at 7:35 PM, Asmusr said: I use the weapon to see the frame rate. Ok. The weapon should move up and down more slowly as you walk. And the weapon should be still, when you stand still or turn (without walking). Quote Link to comment Share on other sites More sharing options...
sometimes99er Posted May 30, 2020 Share Posted May 30, 2020 I suggest a color scheme more along these lines ... 1 Quote Link to comment Share on other sites More sharing options...
Asmusr Posted May 30, 2020 Author Share Posted May 30, 2020 I agree that the floor color has to change, so I have used the yellows that I don't use anywhere else. And I have fixed the gun movement. raycaster.dsk raycaster.rpk raycaster8.bin 11 1 Quote Link to comment Share on other sites More sharing options...
Tursi Posted May 30, 2020 Share Posted May 30, 2020 Witchcraft. 1 1 Quote Link to comment Share on other sites More sharing options...
+Vorticon Posted May 30, 2020 Share Posted May 30, 2020 Does this require the F18A? Quote Link to comment Share on other sites More sharing options...
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