New demo uploaded: Pirate Kingdoms

[rje]

My first steps will be careful ones.... I've never done sprite programming using CC65.

 

[rje]

Updated with some more vision statementy things.

 

I. A PRETTY MAP

• 
  Rounded coastlines, no overlapping sprites.
  

II. AN ECOLOGY

• 
  (1602) Terrain squares have their own characteristics, which define what can be grown on them.
  


• 
  (1602, 7 Cities of Gold) Settlements produce people, supplies, ships, trade goods.  Some are better at self-defense.  They can be owned, and can rebel.
  

• 
  (7 Cities of Gold) A "soft empire" model, based on relationships between settlements.
  


• 
  (1602, 7 Cities of Gold) Establish and dismantle settlements.
  


• 
  (Pirates, 7 Cities of Gold) Barter with or plunder settlements.
  


• 
  (7 Cities of Gold) Explore.
  

 

[rje]

OK, replaced the BASIC version with the C version.  It's more responsive, but the scrolling is terrible.  Also I don't like the way I did the map.  I have to rethink things and use fewer sprites if possible.

 

For example, I use sprites to tile the ocean.  I shouldn't have to do that -- surely I can just use characters to represent the ocean.  Like a reverse period, or something. 

Then, the land sprites themselves are memory hungry.  Each one is 64 x 64 and 8 bit pixels -- 4K!  Oink!  

I think I need to go back to using "coastline" sprites for the edges.  8 x 64 and 64 x 8 sprites.  We'll see.

 

And even after all that, there does appear to be an obvious redraw going on when the ship moves: the sprites appear to stagger.  In other words, C is not fast enough.

[SlithyMatt]

Mainly, you need to make sure you are doing the scrolling during VBLANK by putting it at the beginning of your VSYNC interrupt routine. That should clean it up a lot.

[rje]

On 1/26/2022 at 9:36 AM, SlithyMatt said:

Mainly, you need to make sure you are doing the scrolling during VBLANK by putting it at the beginning of your VSYNC interrupt routine. That should clean it up a lot.

You can do that in C?

[SlithyMatt]

On 1/26/2022 at 2:08 PM, rje said:

You can do that in C?

I should hope so! You may just need some inline assembly to overwrite the IRQ vector with a function address, but you may be able to do that in pure C. 

[pzembrod]

You could also develop this in the direction of the Flying Spaghetti Monster game - fsmgame.com

[ZeroByte]

I forget exactly every step I did in Flappy Bird, but it does IRQ handling in C.

Basically, I made a #define that makes the IRQ vector in RAM ($030-something)  so it looks like a variable, and then I did an inline assembly to SEI, then IRQ_VECTOR = &irq_handler;

Something akin to that.

[svenvandevelde]

Very nice demo. Curious how you created the dynamic tile algorithm.

[rje]

On 1/29/2022 at 4:09 AM, svenvandevelde said:

Very nice demo. Curious how you created the dynamic tile algorithm.

I overlapped the sprites significantly -- 8 pixels on every edge I think.  

The result was absolutely horrible refresh.

 

Today I got rid of the overlap and reverted to plain square sprites instead of ones with contoured shorelines.  It looks uglier but moves MUCH MUCH smoother.

The current view is only a bit more than 5 x 6 "squares".  I also added a regional map view -- typing 'm' draws a 50 x 50 PETSCII map.  That helps get my bearings, so to speak.  I might instead just have a 20 x 20 mini-map on a corner of the normal view.