Well, it's in spanish but it tries to explain graphically; in fact it helped a lot to advance an isometric engine, and moreover, the related inner workings when a limited system is involved.
![Image](https://i.postimg.cc/Jy66ZD2N/Perspectiva-Isom-trica-Mi-An-lisis.png)
Alien Evolution was "reverse engineered" from Ant Attack disassembly.druellan wrote: ↑Tue Jan 21, 2020 7:23 pm And Alien Evolution has a similar style, not sure if it uses the same technique: https://spectrumcomputing.co.uk/index.php?cat=96&id=149
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Alas I can't read Spanish, but to the extent that it's relevant, in each 8x4 block where your document appears to discuss the disadvantages of allocating pixels like:Gilberto wrote: ↑Fri Jun 11, 2021 10:41 am Slightly off topic but strongly related to the artistic techniques employed, I wanted to add this little study me and a friend did to better understand the graphics generation in isometric landscapes.
Well, it's in spanish but it tries to explain graphically; in fact it helped a lot to advance an isometric engine, and moreover, the related inner workings when a limited system is involved.
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I think we get enough of that sort of thing from Ͼ64 owners thank you very much...
I had a quick think about this with the way that my code works, and here's a neat thing: if you either used 8x16-sized steps, or restricted yourself to a 128kb machine for 4x8, you could do full colour by writing to the attributes only. No changes to the actual frame buffer are necessary until you introduce sprites.
This does only update the attributes. The pixel screen is just a grid full of triangles.Tommo wrote: ↑Wed Jun 16, 2021 8:01 pm I had a quick think about this with the way that my code works, and here's a neat thing: if you either used 8x16-sized steps, or restricted yourself to a 128kb machine for 4x8, you could do full colour by writing to the attributes only. No changes to the actual frame buffer are necessary until you introduce sprites.
And, for the avoidance of doubt, completely beyond me.Joefish wrote: ↑Wed Jun 16, 2021 8:20 pm Thing is, your 128K routine either has less than half of the running time it had before while the CPU manages the multicolour effect, or you need to write your routine so that it runs in EXACTLY 912 CPU-clock-tick time-slices with no flexibility, and avoids writing to the attribute memory during 128 of every 228 clock cycles to avoid memory contention delays, so that it can swap between the two screen banks bang-on time to get the extra attribute resolution. That would be impressive.
How were you planning on achieving 8x4 pixel precision with your colour-setting function on a 128K machine? The attributes are still 8x8.
Given code that contains an awful lot of conditional checks, and that the results of it ARE attributes so they WILL be written to contended memory, this could well be in consideration for understatement of the year!
Interesting question, and a good point. Assuming you can limit the map to just the squares you need, each byte of the original map occupies four triangles on the new map, which averages out to two 8x4 attribute bytes. So the map now takes up 32K plus a little more for the piles of blocks that stick up off the top of the floorplan. If you want a rectangular map version rather than a trimmed diamond shape then it's 1.4 times that, so maybe a full 48K all-in. So yes, you could pre-process the entire map into 2 x Attributes, and from two different angles as well, but not the whole thing from four angles.
I was at error — I neglected to think about multiway scrolling. I'd need a machine with four screen buffers, not two.