From 7b9bb772cacc12fba2b3db2da58f271e7753c63b Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Fri, 28 Sep 2018 21:03:51 -0400
Subject: [PATCH] Corrected to give a not-exactly-indexed-correctly
 approximation of what's on display.

---
 Components/9918/9918.cpp                    | 14 ++++++++++++--
 Components/9918/Implementation/9918Base.hpp |  4 ++--
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/Components/9918/9918.cpp b/Components/9918/9918.cpp
index 157250239..b69eb3922 100644
--- a/Components/9918/9918.cpp
+++ b/Components/9918/9918.cpp
@@ -436,9 +436,19 @@ void TMS9918::run_for(const HalfCycles cycles) {
 						case LineMode::SMS: {
 							if(pixel_target_) {
 								const int pixels_left = pixels_end - output_column_;
-								int pixel_location = output_column_ - first_pixel_column_;
+								const int pixel_location = output_column_ - first_pixel_column_;
 								for(int c = 0; c < pixels_left; ++c) {
-									pixel_target_[c] = *(uint32_t *)master_system_.tile_graphics[pixel_location >> 8];
+									const int column = (pixel_location + c) >> 3;
+									const int shift = 4 + ((pixel_location + c) & 7);
+									int value =
+									((
+										((master_system_.tile_graphics[column][0] << shift) & 0x800) |
+										((master_system_.tile_graphics[column][1] << (shift - 1)) & 0x400) |
+										((master_system_.tile_graphics[column][2] << (shift - 2)) & 0x200) |
+										(master_system_.tile_graphics[column][3] << (shift - 3))
+									) >> 8) << 4;
+
+									pixel_target_[c] = (value << 24) | (value << 16) | (value << 8) | value;
 								}
 								pixel_target_ += pixels_left;
 							}
diff --git a/Components/9918/Implementation/9918Base.hpp b/Components/9918/Implementation/9918Base.hpp
index 905289ff5..b9acf0a47 100644
--- a/Components/9918/Implementation/9918Base.hpp
+++ b/Components/9918/Implementation/9918Base.hpp
@@ -218,7 +218,7 @@ class Base {
 #define fetch_tile_name(column)	{\
 		size_t address = pattern_address_base + ((column) << 1);	\
 		master_system_.names[column].flags = ram_[address+1];	\
-		master_system_.names[column].offset = static_cast<size_t>((master_system_.names[column].flags&1 | ram_[address]) << 5) + sub_row;	\
+		master_system_.names[column].offset = static_cast<size_t>((((master_system_.names[column].flags&1) << 8) | ram_[address]) << 5) + sub_row;	\
 	}
 
 #define fetch_tile(column)	{\
@@ -265,7 +265,7 @@ class Base {
 		- column n+3, tile graphic first word
 		- column n+3, tile graphic second word
 */
-			const size_t pattern_address_base = (pattern_name_address_ | size_t(0x3ff)) & static_cast<size_t>(((row_ & ~7) << 6) | 0x3800);
+			const size_t pattern_address_base = (pattern_name_address_ | size_t(0x3ff)) & static_cast<size_t>(((row_ & ~7) << 3) | 0x3800);
 			const size_t sub_row = static_cast<size_t>((row_ & 7) << 2);
 
 			switch(start) {