diff options
| -rw-r--r-- | vdp.c | 22 |
1 files changed, 14 insertions, 8 deletions
@@ -440,12 +440,12 @@ void external_slot(vdp_context * context) void read_map_scroll(uint16_t column, uint16_t vsram_off, uint32_t line, uint16_t address, uint16_t hscroll_val, vdp_context * context) { - /*if (context->double_res) { + if (context->double_res) { line *= 2; if (context->framebuf != context->oddbuf) { line++; } - }*/ + } if (!vsram_off) { uint16_t left_col, right_col; if (context->regs[REG_WINDOW_H] & WINDOW_RIGHT) { @@ -507,14 +507,20 @@ void read_map_scroll(uint16_t column, uint16_t vsram_off, uint32_t line, uint16_ vscroll = 0x3FF; break; } - /*if (context->double_res) { + uint16_t v_offset_mask, vscroll_shift; + if (context->double_res) { vscroll <<= 1; vscroll |= 1; - }*/ + v_offset_mask = 0xF; + vscroll_shift = 4; + } else { + v_offset_mask = 0x7; + vscroll_shift = 3; + } vscroll &= (context->vsram[(context->regs[REG_MODE_3] & BIT_VSCROLL ? column : 0) + vsram_off] + line); - context->v_offset = vscroll & 0x7; + context->v_offset = vscroll & v_offset_mask; //printf("%s | line %d, vsram: %d, vscroll: %d, v_offset: %d\n",(vsram_off ? "B" : "A"), line, context->vsram[context->regs[REG_MODE_3] & 0x4 ? column : 0], vscroll, context->v_offset); - vscroll /= 8; + vscroll >>= vscroll_shift; uint16_t hscroll_mask; uint16_t v_mul; switch(context->regs[REG_SCROLL] & 0x3) @@ -575,9 +581,9 @@ void render_map(uint16_t col, uint8_t * tmp_buf, vdp_context * context) add = 0; } if (col & MAP_BIT_V_FLIP) { - address += 28 - 4 * ((context->v_offset << shift) + add); + address += 28 - 4 * context->v_offset/*((context->v_offset << shift) + add)*/; } else { - address += 4 * ((context->v_offset << shift) + add); + address += 4 * context->v_offset/*((context->v_offset << shift) + add)*/; } uint16_t pal_priority = (col >> 9) & 0x70; int32_t dir; |