pongsagon vichit

Amateur ASIC/FPGA designer building gaming hardware & GPUs. Write a 3D rasterizer on an MCU. Retro PC enthusiast. Teaching graphics programming by day.

[pongsagon vichit @MattDIYgraphics]

TinyGPU v3.0 is coming with a programmable Pixel Shader!!
Tested on FPGA and submitted to the #TinyTapeout May shuttle (~290k transistors).
This Chameleon demo is a tribute to the #GeForce 3, the first programmable GPU released 25 years ago. https://t.co/GCy7tmGfUA

[pongsagon vichit @MattDIYgraphics]

@BreakingTaps @r0b0t_sp1der Oh so your chip is not RISCV. Wow building a compiler would be a hugh task. It is so cool that you can build the whole tech stack. 👍

[pongsagon vichit @MattDIYgraphics]

@BreakingTaps @r0b0t_sp1der Great. Congrat on your chip. What are you planning to do with those 1,000 chips?

[pongsagon vichit @MattDIYgraphics]

@BreakingTaps @r0b0t_sp1der Have you also done taped out via TinyTapeout? Is the Physical design of the whole chip more involved than that of the TinyTapeout?

[pongsagon vichit @MattDIYgraphics]

@shapoco Thank you👍

[pongsagon vichit @MattDIYgraphics]

@SNDR_SNDL Oh! So it cannot render transparency sprite?

[pongsagon vichit @MattDIYgraphics]

@ichiken_make Oh My God. You have an Open source asic chip design magazine?

[pongsagon vichit @MattDIYgraphics]

@MartinPiper Cool. 👍

[pongsagon vichit @MattDIYgraphics]

@Ryuz88 Agree. For the individual ASIC fab, I think it is about 40 years ago, ex. i386 CPU. I also agree that making alternate version of the chip, "things that could have been done", is much more fun than trying to do hardware emulator of the old chip.

[pongsagon vichit @MattDIYgraphics]

@MartinPiper @ModernVintageG Thank you

[pongsagon vichit @MattDIYgraphics]

@MartinPiper @ModernVintageG Thanks. Do you have a ref/link to the buffer visualization of Sega X board. I mean I would like to know in term of the game design. How many rotation/scaling image for each sprite. Or how they arrange those sprite on the screen space.

[pongsagon vichit @MattDIYgraphics]

@dydt_Nao @S_Okue Nice work on this charming retro tech.

[pongsagon vichit @MattDIYgraphics]

@pikuma Please develop Quake-style engine on this NeXT machine as your next YouTube tutorial video. It is going to be Super Cool.

[pongsagon vichit @MattDIYgraphics]

@Kuratius Yeah, I have no plan of writing an Assembler for my shader. Writing an assembler is not too hard actually, but it is super not fun to write.
For this super small shader, writing in hex also gives you the ASMR, minimal zen like feeling.

[pongsagon vichit @MattDIYgraphics]

TinyGPU v3.0 Pixel Shader spec:
• lightweight DirectX 8 PS 1.1–inspired design
• SIMD (4 pixels in parallel)
• 31 instructions per shader (tweaking)
• 26-op instruction set
• Branching via masked execution
• 4× 8-bit temp registers

[pongsagon vichit @MattDIYgraphics]

@Kuratius This TinyGPU is so minimal in terms of capabilities and performance. It does not come close to supporting standard graphics/gpu API.

[pongsagon vichit @MattDIYgraphics]

@SebAaltonen Thanks. Early-z and hierarchical-z are really cool. For this TinyTapeout GPU, my biggest hurdles are the suffocatingly narrow memory bandwidth and the tiny amount of on-chip cache.

[pongsagon vichit @MattDIYgraphics]

Every pixel needs a depth test, but RAM is slow.

TinyGPU v3.0 hides that latency by running shader execution in parallel with Z-buffer access.

That jump—from a fixed pipeline in v2.0 to a 31-instruction pixel shader core in v3.0—happens without dropping a single frame 🚀