3 ms·

What does pseudo 3D vs video based approach mean for these games?

throwaway0665 2y ago
You draw the 2D projection of 3D objects manually instead of drawing 3D geometry and the hardware draws the 2D projection to the screen. The other is the gameplay is a video of a 3D scene that has been prerendered on a more powerful machine.
- MBCook 2y ago
  So essentially an FMV game, but used to provide better 3D than the system ever could natively instead of video of actual people. For a game like this where the path is limited and known that’s a very smart approach. Neat.
  - playworker 2y ago
    Reminds me of MegaRace: https://en.wikipedia.org/wiki/MegaRace https://en.wikipedia.org/wiki/MegaRace
- hbridges 2y ago
  That's exactly right. The issue I ran into is that the Playdate's CPU doesn't have a lot of juice, and spends a lot of time every frame just filling the screen. There's no specialized blitting hardware or GPU. Hence realtime sprite scaling is not feasible. I tried making some pre-scaled sprites, and the ROM footprint had to be pretty large to afford enough size steps for reasonably smooth motion as the train moved past objects. Even then, all that sprite drawing was starting to dip the frame rate. So, I experimented with a pre-rendered approach, and that was a huge unlock. Eventually I was able to wrangle it into something that I think worked even better in the end! The pre-rendered video based approach allowed way more elaborate detail and I didn't have to worry about frame rate anymore.
  - two_handfuls 2y ago
    I'm impressed the video fits!
  - vardump 2y ago
    > Hence realtime sprite scaling is not feasible. Playdate got STM32F746 (ARM Cortex-M7F) at 180 MHz. 320 kB SRAM (and 16 MB of other RAM, maybe PSRAM?). DSP and saturation instructions are included. The display is 400x240 1bpp. Surely that's more than enough juice for sprite scaling? (Might need to copy graphics data to SRAM and even to do it in tiles for better performance.) Although your video based implementation is pretty cool.
    - nickisnoble 2y ago
      I double dog dare you to port doom
      - omoikane 2y ago
        https://news.ycombinator.com/item?id=41013159 https://news.ycombinator.com/item?id=41013159 - Doom on Playdate (2024-07-20, 39 comments)

You draw the 2D projection of 3D objects manually instead of drawing 3D geometry and the hardware draws the 2D projection to the screen. The other is the gameplay is a video of a 3D scene that has been prerendered on a more powerful machine.

MBCook 2y ago
So essentially an FMV game, but used to provide better 3D than the system ever could natively instead of video of actual people. For a game like this where the path is limited and known that’s a very smart approach. Neat.
- playworker 2y ago
  Reminds me of MegaRace: https://en.wikipedia.org/wiki/MegaRace https://en.wikipedia.org/wiki/MegaRace
hbridges 2y ago
That's exactly right. The issue I ran into is that the Playdate's CPU doesn't have a lot of juice, and spends a lot of time every frame just filling the screen. There's no specialized blitting hardware or GPU. Hence realtime sprite scaling is not feasible. I tried making some pre-scaled sprites, and the ROM footprint had to be pretty large to afford enough size steps for reasonably smooth motion as the train moved past objects. Even then, all that sprite drawing was starting to dip the frame rate. So, I experimented with a pre-rendered approach, and that was a huge unlock. Eventually I was able to wrangle it into something that I think worked even better in the end! The pre-rendered video based approach allowed way more elaborate detail and I didn't have to worry about frame rate anymore.
- two_handfuls 2y ago
  I'm impressed the video fits!
- vardump 2y ago
  > Hence realtime sprite scaling is not feasible. Playdate got STM32F746 (ARM Cortex-M7F) at 180 MHz. 320 kB SRAM (and 16 MB of other RAM, maybe PSRAM?). DSP and saturation instructions are included. The display is 400x240 1bpp. Surely that's more than enough juice for sprite scaling? (Might need to copy graphics data to SRAM and even to do it in tiles for better performance.) Although your video based implementation is pretty cool.
  - nickisnoble 2y ago
    I double dog dare you to port doom
    - omoikane 2y ago
      https://news.ycombinator.com/item?id=41013159 https://news.ycombinator.com/item?id=41013159 - Doom on Playdate (2024-07-20, 39 comments)