fvdhoef / vera-module

Versatile Embedded Retro Adapter
MIT License
107 stars 44 forks source link

High V_Scale values don't render as expected #29

Open Yazwh0 opened 1 year ago

Yazwh0 commented 1 year ago

With a high V_Scale value we get what appears to be line 480 copied down the screen. This feels unintuitive. It should either be line 479 (where line 0 is the first line), draw nothing, or should continue to render without the 480 constraint.

So either change this to 479, or remove the check? https://github.com/fvdhoef/vera-module/blob/rev4/fpga/source/graphics/composer.v#L157

image

Test app for above: code: test.zip prg: example.zip

Yazwh0 commented 1 year ago

scaled_y_counter isn't wide enough to hold the max scaled value of 956. (0xff * 480 >> 7) If that cannot be widened I guess second most preferable result would be that it would work like high H_Scale values where it renders colour 0?