[nostalgia/core/userland] Fix Tile row skipping and move some non-SDL code into userland

src/nostalgia/core/userland/gfx.cpp

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2016 - 2021 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/claw/claw.hpp>
+#include <nostalgia/core/gfx.hpp>
+#include <nostalgia/core/gfx.hpp>
+
+#include "gfx.hpp"
+
+namespace nostalgia::core {
+
+static ox::Result<ox::Vector<char>> readFile(Context *ctx, const ox::FileAddress &file) {
+	oxRequire(stat, ctx->rom->stat(file));
+	ox::Vector<char> buff(stat.size);
+	oxReturnError(ctx->rom->read(file, buff.data(), buff.size()));
+	return buff;
+}
+
+template<typename T>
+ox::Result<T> readObj(Context *ctx, const ox::FileAddress &file) {
+	oxRequire(buff, readFile(ctx, file));
+	T t;
+	oxReturnError(ox::readClaw(buff.data(), buff.size(), &t));
+	return t;
+}
+
+ox::Error initConsole(Context *ctx) {
+	constexpr auto TilesheetAddr = "/TileSheets/Charset.ng";
+	return loadBgTileSheet(ctx, 0, TilesheetAddr);
+}
+
+ox::Error loadSpriteTileSheet(Context*,
+                              int,
+                              ox::FileAddress,
+                              ox::FileAddress) {
+	return OxError(0);
+}
+
+ox::Error loadBgTileSheet(Context *ctx,
+                          int section,
+                          ox::FileAddress tilesheetPath,
+                          ox::FileAddress palettePath) {
+	oxRequire(tilesheet, readObj<NostalgiaGraphic>(ctx, tilesheetPath));
+	if (!palettePath) {
+		palettePath = tilesheet.defaultPalette;
+	}
+	oxRequire(palette, readObj<NostalgiaPalette>(ctx, palettePath));
+	const unsigned bytesPerTile = tilesheet.bpp == 8 ? 64 : 32;
+	const auto tiles = tilesheet.pixels.size() / bytesPerTile;
+	constexpr int width = 8;
+	const int height = 8 * tiles;
+	ox::Vector<uint32_t> pixels;
+	if (bytesPerTile == 64) { // 8 BPP
+		pixels.resize(tilesheet.pixels.size());
+		for (std::size_t i = 0; i < tilesheet.pixels.size(); ++i) {
+			pixels[i] = toColor32(palette.colors[tilesheet.pixels[i]]);
+		}
+	} else { // 4 BPP
+		pixels.resize(tilesheet.pixels.size() * 2);
+		for (std::size_t i = 0; i < tilesheet.pixels.size(); ++i) {
+			pixels[i * 2 + 0] = toColor32(palette.colors[tilesheet.pixels[i] & 0xF]);
+			pixels[i * 2 + 1] = toColor32(palette.colors[tilesheet.pixels[i] >> 4]);
+		}
+	}
+	return renderer::loadBgTexture(ctx, section, pixels.data(), width, height);
+}
+
+}