From 90fbad0f1cc2e960b8f9bb4b3f26dac7b8275d0e Mon Sep 17 00:00:00 2001 From: Thomas Harte Date: Tue, 23 Oct 2018 20:30:08 -0400 Subject: [PATCH] Implements SMS2-style addressing if in a 224 or 240-line mode. This isn't quite accurate, but it'll do for development. --- Components/9918/Implementation/9918Base.hpp | 23 ++++++++++++++------- 1 file changed, 15 insertions(+), 8 deletions(-) diff --git a/Components/9918/Implementation/9918Base.hpp b/Components/9918/Implementation/9918Base.hpp index da688d908..f21a99a88 100644 --- a/Components/9918/Implementation/9918Base.hpp +++ b/Components/9918/Implementation/9918Base.hpp @@ -647,12 +647,12 @@ class Base { #define sprite_fetch(sprite) {\ line_buffer.active_sprites[sprite].x = \ ram_[\ - sprite_attribute_table_address_ & size_t(0x3f80 | (line_buffer.active_sprites[sprite].index << 1))\ + sprite_attribute_table_address & size_t(0x3f80 | (line_buffer.active_sprites[sprite].index << 1))\ ] - (master_system_.shift_sprites_8px_left ? 8 : 0); \ const uint8_t name = ram_[\ - sprite_attribute_table_address_ & size_t(0x3f81 | (line_buffer.active_sprites[sprite].index << 1))\ + sprite_attribute_table_address & size_t(0x3f81 | (line_buffer.active_sprites[sprite].index << 1))\ ] & (sprites_16x16_ ? ~1 : ~0);\ - const size_t graphic_location = sprite_generator_table_address_ & size_t(0x2000 | (name << 5) | (line_buffer.active_sprites[sprite].row << 2)); \ + const size_t graphic_location = sprite_generator_table_address & size_t(0x2000 | (name << 5) | (line_buffer.active_sprites[sprite].row << 2)); \ line_buffer.active_sprites[sprite].image[0] = ram_[graphic_location]; \ line_buffer.active_sprites[sprite].image[1] = ram_[graphic_location+1]; \ line_buffer.active_sprites[sprite].image[2] = ram_[graphic_location+2]; \ @@ -671,8 +671,8 @@ class Base { #define sprite_y_read(location, sprite) \ slot(location): \ - posit_sprite(sprite_selection_buffer, sprite, ram_[sprite_attribute_table_address_ & ((sprite) | 0x3f00)], write_pointer_.row); \ - posit_sprite(sprite_selection_buffer, sprite+1, ram_[sprite_attribute_table_address_ & ((sprite + 1) | 0x3f00)], write_pointer_.row); \ + posit_sprite(sprite_selection_buffer, sprite, ram_[sprite_attribute_table_address & ((sprite) | 0x3f00)], write_pointer_.row); \ + posit_sprite(sprite_selection_buffer, sprite+1, ram_[sprite_attribute_table_address & ((sprite + 1) | 0x3f00)], write_pointer_.row); \ #define fetch_tile_name(column, row_info) {\ const size_t scrolled_column = (column - horizontal_offset) & 0x1f;\ @@ -718,20 +718,27 @@ class Base { LineBuffer &sprite_selection_buffer = line_buffers_[(write_pointer_.row + 1) % mode_timing_.total_lines]; const int horizontal_offset = (write_pointer_.row >= 16 || !master_system_.horizontal_scroll_lock) ? (line_buffer.latched_horizontal_scroll >> 3) : 0; + // Limit address bits in use if this is a SMS2 mode. + const bool is_tall_mode = mode_timing_.pixel_lines != 192; + const size_t pattern_name_address = pattern_name_address_ | (is_tall_mode ? 0xc00 : 0); + const size_t pattern_name_offset = is_tall_mode ? 0x100 : 0; + const size_t sprite_attribute_table_address = sprite_attribute_table_address_ | (is_tall_mode ? 0x80 : 0); + const size_t sprite_generator_table_address = sprite_generator_table_address_ | (is_tall_mode ? 0x1800 : 0); + // Determine row info for the screen both (i) if vertical scrolling is applied; and (ii) if it isn't. // The programmer can opt out of applying vertical scrolling to the right-hand portion of the display. - const int scrolled_row = (write_pointer_.row + master_system_.latched_vertical_scroll) % 224; + const int scrolled_row = (write_pointer_.row + master_system_.latched_vertical_scroll) % (is_tall_mode ? 256 : 224); struct RowInfo { size_t pattern_address_base; size_t sub_row[2]; }; const RowInfo scrolled_row_info = { - pattern_name_address_ & static_cast(((scrolled_row & ~7) << 3) | 0x3800), + pattern_name_address & size_t(((scrolled_row & ~7) << 3) | 0x3800) - pattern_name_offset, {static_cast((scrolled_row & 7) << 2), 28 ^ static_cast((scrolled_row & 7) << 2)} }; RowInfo row_info; if(master_system_.vertical_scroll_lock) { - row_info.pattern_address_base = pattern_name_address_ & static_cast(((write_pointer_.row & ~7) << 3) | 0x3800); + row_info.pattern_address_base = pattern_name_address & size_t(((write_pointer_.row & ~7) << 3) | 0x3800) - pattern_name_offset; row_info.sub_row[0] = size_t((write_pointer_.row & 7) << 2); row_info.sub_row[1] = 28 ^ size_t((write_pointer_.row & 7) << 2); } else row_info = scrolled_row_info;