From 9376413057ac0feede60a215abfde072e07d7570 Mon Sep 17 00:00:00 2001 From: Mike Pavone Date: Sat, 8 Dec 2012 20:25:56 -0800 Subject: Make horizontal scrolling closer to correct, Comix Zone looks good, Sonic 2 slightly off --- vdp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'vdp.c') diff --git a/vdp.c b/vdp.c index ac26f62..5ee2de2 100644 --- a/vdp.c +++ b/vdp.c @@ -180,7 +180,7 @@ void read_map_scroll(uint16_t column, uint16_t vsram_off, uint32_t line, uint16_ } uint16_t hscroll, offset; for (int i = 0; i < 2; i++) { - hscroll = (hscroll_val + (column + i) * 8) & hscroll_mask; + hscroll = ((column - 2 + i) * 8 - hscroll_val) & hscroll_mask; offset = address + ((vscroll * v_mul + hscroll/4) & 0x1FFF); //printf("%s | line: %d, col: %d, x: %d, hs_mask %X, v_mul: %d, scr reg: %X, tbl addr: %X\n", (vsram_off ? "B" : "A"), line, (column-(2-i)), hscroll, hscroll_mask, v_mul, context->regs[REG_SCROLL], offset); uint16_t col_val = (context->vdpmem[offset] << 8) | context->vdpmem[offset+1]; -- cgit v1.2.3