summaryrefslogtreecommitdiff
path: root/src/librosprite.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/librosprite.c')
-rw-r--r--src/librosprite.c866
1 files changed, 866 insertions, 0 deletions
diff --git a/src/librosprite.c b/src/librosprite.c
new file mode 100644
index 0000000..9252510
--- a/dev/null
+++ b/src/librosprite.c
@@ -0,0 +1,866 @@
+/*
+ * This file is part of librosprite.
+ * Licensed under the MIT License,
+ * http://www.opensource.org/licenses/mit-license.php
+ * Copyright 2008 James Shaw <js102@zepler.net>
+ */
+
+/**
+ * \file
+ */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
+
+#include "librosprite.h"
+
+/**
+ * Reads four bytes, 00, 11, 22 and 33, of a byte array b to give 0x33221100.
+ */
+#define BTUINT(b) (b[0] | (b[1] << 8) | (b[2] << 16) | (b[3] << 24))
+
+/**
+ * Reverse the byte order of a word such that 0xAABBCCDD becomes 0xDDCCBBAA.
+ */
+#define BSWAP(word) (((word & (0x000000ff)) << 24) | ((word & 0x0000ff00) << 8) | ((word & 0x00ff0000) >> 8) | ((word & 0xff000000) >> 24))
+
+#define ERRCHK(x) do { \
+ rosprite_error err = x; \
+ if (err != ROSPRITE_OK) return err; \
+} while(0)
+
+struct rosprite_header {
+ uint32_t width_words; /* width in words */
+ /* height defined in sprite struct */
+ uint32_t first_used_bit; /* old format only (spriteType = 0) */
+ uint32_t last_used_bit;
+
+ /**
+ * Image size in bytes
+ */
+ uint32_t image_size;
+
+ /**
+ * Mask size in bytes
+ */
+ uint32_t mask_size;
+};
+
+struct rosprite_mask_state {
+ uint32_t x;
+ uint32_t y;
+ uint32_t first_used_bit;
+ uint32_t row_max_bit;
+ uint32_t height;
+ uint32_t current_byte_index;
+ uint32_t current_word;
+ uint32_t bpp;
+};
+
+struct rosprite_file_context {
+ FILE* f;
+};
+
+struct rosprite_mem_context {
+ uint8_t* base;
+ unsigned long offset;
+ bool known_size;
+ unsigned long size;
+};
+
+static const struct rosprite_mode oldmodes[] = {
+/*0*/{ .colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*1*/{ .colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 45, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*2*/{ .colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 22, .ydpi = 45, .color_model = ROSPRITE_RGB },
+
+/*3*/{ .colorbpp = 0, .maskbpp = 0, .mask_width = 0, .xdpi = 0, .ydpi = 0, .color_model = ROSPRITE_RGB },
+
+/*4*/{ .colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 45, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*5*/{ .colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 22, .ydpi = 45, .color_model = ROSPRITE_RGB },
+
+/*6*/{ .colorbpp = 0, .maskbpp = 0, .mask_width = 0, .xdpi = 0, .ydpi = 0, .color_model = ROSPRITE_RGB },
+/*7*/{ .colorbpp = 0, .maskbpp = 0, .mask_width = 0, .xdpi = 0, .ydpi = 0, .color_model = ROSPRITE_RGB },
+
+/*8*/{ .colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*9*/{ .colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 45, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*10*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 22, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*11*/{.colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*12*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*13*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 45, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*14*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*15*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*16*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*17*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*18*/{.colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*19*/{.colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*20*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*21*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*22*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi =180, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*23*/{.colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*24*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*25*/{.colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*26*/{.colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*27*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*28*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*29*/{.colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*30*/{.colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*31*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*32*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 90, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*33*/{.colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*34*/{.colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*35*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*36*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*37*/{.colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*38*/{.colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*39*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*40*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*41*/{.colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*42*/{.colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*43*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*44*/{.colorbpp = 1, .maskbpp = 1, .mask_width = 1, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*45*/{.colorbpp = 2, .maskbpp = 1, .mask_width = 2, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*46*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 90, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*47*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 45, .ydpi = 45, .color_model = ROSPRITE_RGB },
+/*48*/{.colorbpp = 4, .maskbpp = 1, .mask_width = 4, .xdpi = 45, .ydpi = 90, .color_model = ROSPRITE_RGB },
+/*49*/{.colorbpp = 8, .maskbpp = 1, .mask_width = 8, .xdpi = 45, .ydpi = 90, .color_model = ROSPRITE_RGB }
+};
+
+/* table for converting a 5bit channel into an 8bit channel (used for 16bpp to 32bpp conversion) */
+static const uint8_t sprite_16bpp_translate[] = {
+ 0x00, 0x08, 0x10, 0x18, 0x20, 0x29, 0x31, 0x39,
+ 0x41, 0x4a, 0x52, 0x5a, 0x62, 0x6a, 0x73, 0x7b,
+ 0x83, 0x8b, 0x94, 0x9c, 0xa4, 0xac, 0xb4, 0xbd,
+ 0xc5, 0xcd, 0xd5, 0xde, 0xe6, 0xee, 0xf6, 0xff
+};
+
+/* palettes generated with palette2c.c
+ * which in turn requires rosprite_load_palette(FILE* f)
+ * defined in this file
+ */
+static const uint32_t sprite_1bpp_palette[] = { 0xffffffff, 0xff };
+
+static const uint32_t sprite_2bpp_palette[] = { 0xffffffff, 0xbbbbbbff, 0x777777ff, 0xff };
+
+static const uint32_t sprite_4bpp_palette[] = {
+0xffffffff, 0xddddddff, 0xbbbbbbff, 0x999999ff,
+0x777777ff, 0x555555ff, 0x333333ff, 0xff,
+0x4499ff, 0xeeee00ff, 0xcc00ff, 0xdd0000ff,
+0xeeeebbff, 0x558800ff, 0xffbb00ff, 0xbbffff
+};
+
+static const uint32_t sprite_8bpp_palette[] = {
+0xff, 0x111111ff, 0x222222ff, 0x333333ff,
+0x440000ff, 0x551111ff, 0x662222ff, 0x773333ff,
+0x44ff, 0x111155ff, 0x222266ff, 0x333377ff,
+0x440044ff, 0x551155ff, 0x662266ff, 0x773377ff,
+0x880000ff, 0x991111ff, 0xaa2222ff, 0xbb3333ff,
+0xcc0000ff, 0xdd1111ff, 0xee2222ff, 0xff3333ff,
+0x880044ff, 0x991155ff, 0xaa2266ff, 0xbb3377ff,
+0xcc0044ff, 0xdd1155ff, 0xee2266ff, 0xff3377ff,
+0x4400ff, 0x115511ff, 0x226622ff, 0x337733ff,
+0x444400ff, 0x555511ff, 0x666622ff, 0x777733ff,
+0x4444ff, 0x115555ff, 0x226666ff, 0x337777ff,
+0x444444ff, 0x555555ff, 0x666666ff, 0x777777ff,
+0x884400ff, 0x995511ff, 0xaa6622ff, 0xbb7733ff,
+0xcc4400ff, 0xdd5511ff, 0xee6622ff, 0xff7733ff,
+0x884444ff, 0x995555ff, 0xaa6666ff, 0xbb7777ff,
+0xcc4444ff, 0xdd5555ff, 0xee6666ff, 0xff7777ff,
+0x8800ff, 0x119911ff, 0x22aa22ff, 0x33bb33ff,
+0x448800ff, 0x559911ff, 0x66aa22ff, 0x77bb33ff,
+0x8844ff, 0x119955ff, 0x22aa66ff, 0x33bb77ff,
+0x448844ff, 0x559955ff, 0x66aa66ff, 0x77bb77ff,
+0x888800ff, 0x999911ff, 0xaaaa22ff, 0xbbbb33ff,
+0xcc8800ff, 0xdd9911ff, 0xeeaa22ff, 0xffbb33ff,
+0x888844ff, 0x999955ff, 0xaaaa66ff, 0xbbbb77ff,
+0xcc8844ff, 0xdd9955ff, 0xeeaa66ff, 0xffbb77ff,
+0xcc00ff, 0x11dd11ff, 0x22ee22ff, 0x33ff33ff,
+0x44cc00ff, 0x55dd11ff, 0x66ee22ff, 0x77ff33ff,
+0xcc44ff, 0x11dd55ff, 0x22ee66ff, 0x33ff77ff,
+0x44cc44ff, 0x55dd55ff, 0x66ee66ff, 0x77ff77ff,
+0x88cc00ff, 0x99dd11ff, 0xaaee22ff, 0xbbff33ff,
+0xcccc00ff, 0xdddd11ff, 0xeeee22ff, 0xffff33ff,
+0x88cc44ff, 0x99dd55ff, 0xaaee66ff, 0xbbff77ff,
+0xcccc44ff, 0xdddd55ff, 0xeeee66ff, 0xffff77ff,
+0x88ff, 0x111199ff, 0x2222aaff, 0x3333bbff,
+0x440088ff, 0x551199ff, 0x6622aaff, 0x7733bbff,
+0xccff, 0x1111ddff, 0x2222eeff, 0x3333ffff,
+0x4400ccff, 0x5511ddff, 0x6622eeff, 0x7733ffff,
+0x880088ff, 0x991199ff, 0xaa22aaff, 0xbb33bbff,
+0xcc0088ff, 0xdd1199ff, 0xee22aaff, 0xff33bbff,
+0x8800ccff, 0x9911ddff, 0xaa22eeff, 0xbb33ffff,
+0xcc00ccff, 0xdd11ddff, 0xee22eeff, 0xff33ffff,
+0x4488ff, 0x115599ff, 0x2266aaff, 0x3377bbff,
+0x444488ff, 0x555599ff, 0x6666aaff, 0x7777bbff,
+0x44ccff, 0x1155ddff, 0x2266eeff, 0x3377ffff,
+0x4444ccff, 0x5555ddff, 0x6666eeff, 0x7777ffff,
+0x884488ff, 0x995599ff, 0xaa66aaff, 0xbb77bbff,
+0xcc4488ff, 0xdd5599ff, 0xee66aaff, 0xff77bbff,
+0x8844ccff, 0x9955ddff, 0xaa66eeff, 0xbb77ffff,
+0xcc44ccff, 0xdd55ddff, 0xee66eeff, 0xff77ffff,
+0x8888ff, 0x119999ff, 0x22aaaaff, 0x33bbbbff,
+0x448888ff, 0x559999ff, 0x66aaaaff, 0x77bbbbff,
+0x88ccff, 0x1199ddff, 0x22aaeeff, 0x33bbffff,
+0x4488ccff, 0x5599ddff, 0x66aaeeff, 0x77bbffff,
+0x888888ff, 0x999999ff, 0xaaaaaaff, 0xbbbbbbff,
+0xcc8888ff, 0xdd9999ff, 0xeeaaaaff, 0xffbbbbff,
+0x8888ccff, 0x9999ddff, 0xaaaaeeff, 0xbbbbffff,
+0xcc88ccff, 0xdd99ddff, 0xeeaaeeff, 0xffbbffff,
+0xcc88ff, 0x11dd99ff, 0x22eeaaff, 0x33ffbbff,
+0x44cc88ff, 0x55dd99ff, 0x66eeaaff, 0x77ffbbff,
+0xccccff, 0x11ddddff, 0x22eeeeff, 0x33ffffff,
+0x44ccccff, 0x55ddddff, 0x66eeeeff, 0x77ffffff,
+0x88cc88ff, 0x99dd99ff, 0xaaeeaaff, 0xbbffbbff,
+0xcccc88ff, 0xdddd99ff, 0xeeeeaaff, 0xffffbbff,
+0x88ccccff, 0x99ddddff, 0xaaeeeeff, 0xbbffffff,
+0xccccccff, 0xddddddff, 0xeeeeeeff, 0xffffffff
+};
+
+static inline rosprite_error rosprite_read_word(reader reader, void* ctx, uint32_t* result);
+static rosprite_error rosprite_get_mode(uint32_t spriteMode, struct rosprite_mode* result);
+static uint32_t rosprite_palette_lookup(struct rosprite* sprite, uint32_t pixel);
+static inline uint32_t rosprite_cmyk_to_rgb(uint32_t cmyk);
+static uint32_t rosprite_next_mask_pixel(uint8_t* mask, struct rosprite_mask_state* mask_state);
+static rosprite_error rosprite_load_high_color(uint8_t* image_in, uint8_t* mask, struct rosprite* sprite, struct rosprite_header* header);
+static rosprite_error rosprite_load_low_color(uint8_t* image_in, uint8_t* mask, struct rosprite* sprite, struct rosprite_header* header);
+rosprite_error rosprite_load_sprite(reader reader, void* ctx, struct rosprite** result);
+static rosprite_error rosprite_init_mask_state(struct rosprite* sprite, struct rosprite_header* header, uint8_t* mask, struct rosprite_mask_state** result);
+static uint32_t rosprite_upscale_color(uint32_t pixel, struct rosprite_mode* mode, bool* has_alpha_pixel_data);
+static inline void rosprite_fix_alpha(uint32_t* image, unsigned long pixels);
+
+rosprite_error rosprite_load(reader reader, void* ctx, struct rosprite_area** result)
+{
+ uint32_t firstSpriteOffset, firstFreeWordOffset;
+ int bytes_read;
+ uint32_t i;
+
+ struct rosprite_area* sprite_area = malloc(sizeof(struct rosprite_area));
+
+ ERRCHK(rosprite_read_word(reader, ctx, &(sprite_area->sprite_count)));
+
+ ERRCHK(rosprite_read_word(reader, ctx, &firstSpriteOffset));
+ ERRCHK(rosprite_read_word(reader, ctx, &firstFreeWordOffset)); /* TODO: use this for some sanity checking? */
+ sprite_area->extension_size = 16 - firstSpriteOffset;
+
+ sprite_area->extension_words = NULL;
+ if (sprite_area->extension_size > 0) {
+ sprite_area->extension_words = malloc(sprite_area->extension_size);
+ bytes_read = reader(sprite_area->extension_words, (size_t) (sprite_area->extension_size), ctx);
+ if (bytes_read < (signed long) sprite_area->extension_size) {
+ return ROSPRITE_EOF;
+ }
+ }
+
+ sprite_area->sprites = malloc(sizeof(struct rosprite*) * sprite_area->sprite_count); /* allocate array of pointers */
+ for (i = 0; i < sprite_area->sprite_count; i++) {
+ struct rosprite* sprite;
+ ERRCHK(rosprite_load_sprite(reader, ctx, &sprite));
+ sprite_area->sprites[i] = sprite;
+ }
+
+ *result = sprite_area;
+
+ return ROSPRITE_OK;
+}
+
+void rosprite_destroy_sprite_area(struct rosprite_area* sprite_area)
+{
+ uint32_t i;
+ for (i = 0; i < sprite_area->sprite_count; i++) {
+ struct rosprite* sprite = sprite_area->sprites[i];
+ if (sprite->has_palette) free(sprite->palette);
+ free(sprite->image);
+ free(sprite);
+ }
+
+ free(sprite_area->sprites);
+ if (sprite_area->extension_size > 0) free(sprite_area->extension_words);
+ free(sprite_area);
+}
+
+rosprite_error rosprite_load_palette(reader reader, void* ctx, struct rosprite_palette** result)
+{
+ uint32_t c;
+ uint8_t b[6];
+ unsigned int bytesRead;
+
+ /* TODO: currently assume palette has linear entries (2nd byte in is 00, 01, 02 etc) */
+ struct rosprite_palette* palette = malloc(sizeof(struct rosprite_palette));
+
+ palette->palette = malloc(sizeof(uint32_t) * 256); /* allocate 256 whether we need them all or not */
+
+ c = 0;
+
+ bytesRead = reader(b, 6, ctx);
+ assert(bytesRead % 6 == 0);
+ while (bytesRead == 6) {
+ assert(b[0] == 19); /* VDU 19 */
+
+ /* only process logical colours */
+ if (b[2] == 16) {
+ /*assert(c == b[1]);*/
+
+ uint32_t entry = (b[3] << 24) | (b[4] << 16) | (b[5] << 8) | 0xff; /* last byte is alpha */
+ palette->palette[c] = entry;
+
+ c++;
+ assert(c <= 256);
+ }
+
+ bytesRead = reader(b, 6, ctx);
+ assert(bytesRead % 6 == 0);
+ }
+
+ palette->size = c;
+
+ *result = palette;
+
+ return ROSPRITE_OK;
+}
+
+void rosprite_destroy_palette(struct rosprite_palette* palette)
+{
+ free(palette->palette);
+ free(palette);
+}
+
+rosprite_error rosprite_create_file_context(FILE* f, struct rosprite_file_context** result)
+{
+ struct rosprite_file_context* ctx = malloc(sizeof(struct rosprite_file_context));
+ if (!ctx) return ROSPRITE_NOMEM;
+ ctx->f = f;
+ *result = ctx;
+
+ return ROSPRITE_OK;
+}
+
+void rosprite_destroy_file_context(struct rosprite_file_context* ctx)
+{
+ free(ctx);
+}
+
+int rosprite_file_reader(uint8_t* buf, size_t count, void* ctx)
+{
+ return fread(buf, 1 /*size*/, count, ((struct rosprite_file_context*) ctx)->f);
+}
+
+rosprite_error rosprite_create_mem_context(uint8_t* p, unsigned long total_size, struct rosprite_mem_context** result)
+{
+ struct rosprite_mem_context* ctx = malloc(sizeof(struct rosprite_mem_context));
+ if (!ctx) return ROSPRITE_NOMEM;
+
+ ctx->base = p;
+ ctx->offset = 0;
+ ctx->size = total_size;
+ *result = ctx;
+
+ return ROSPRITE_OK;
+}
+
+void rosprite_destroy_mem_context(struct rosprite_mem_context* ctx)
+{
+ free(ctx);
+}
+
+int rosprite_mem_reader(uint8_t* buf, size_t count, void* ctx)
+{
+ size_t copy_size;
+ struct rosprite_mem_context* memctx = (struct rosprite_mem_context*) ctx;
+ if (memctx->offset + count > memctx->size) {
+ return -1;
+ }
+
+ // if we're asked for more memory than the block contains, only copy as much as we can
+ if ((memctx->offset + count) > memctx->size) {
+ copy_size = memctx->size - memctx->offset;
+ } else {
+ copy_size = count;
+ }
+ memcpy(buf, memctx->base + memctx->offset, count);
+ memctx->offset += count;
+ return copy_size;
+}
+
+/**
+ * Load a single sprite.
+ *
+ * \param[out] result
+ */
+rosprite_error rosprite_load_sprite(reader reader, void* ctx, struct rosprite** result)
+{
+ uint32_t nextSpriteOffset;
+ uint32_t imageOffset;
+ uint32_t maskOffset, spriteModeWord;
+ uint32_t paletteEntries;
+ uint8_t* image;
+ uint8_t* mask = NULL;
+
+ struct rosprite* sprite = malloc(sizeof(struct rosprite));
+ struct rosprite_header* header = malloc(sizeof(struct rosprite_header));
+
+ ERRCHK(rosprite_read_word(reader, ctx, &nextSpriteOffset));
+
+ reader(sprite->name, 12, ctx);
+ sprite->name[12] = '\0';
+
+ ERRCHK(rosprite_read_word(reader, ctx, &header->width_words)); /* file has width - 1 and height - 1 */
+ header->width_words += 1;
+ ERRCHK(rosprite_read_word(reader, ctx, &(sprite->height)));
+ sprite->height += 1;
+ ERRCHK(rosprite_read_word(reader, ctx, &(header->first_used_bit))); /* old format only (spriteType = 0) */
+ ERRCHK(rosprite_read_word(reader, ctx, &(header->last_used_bit)));
+
+ ERRCHK(rosprite_read_word(reader, ctx, &imageOffset));
+ assert(imageOffset >= 44); /* should never be smaller than the size of the header) */
+
+ ERRCHK(rosprite_read_word(reader, ctx, &maskOffset));
+ ERRCHK(rosprite_read_word(reader, ctx, &spriteModeWord));
+
+ ERRCHK(rosprite_get_mode(spriteModeWord, &(sprite->mode)));
+
+ /* TODO left-hand wastage */
+
+ assert((header->last_used_bit + 1) % sprite->mode.colorbpp == 0);
+ /*assert(header->width_words % sprite->mode->colorbpp == 0);*/
+ sprite->width = (header->width_words * 32 - header->first_used_bit - (31 - header->last_used_bit)) / sprite->mode.colorbpp;
+
+ sprite->palettesize = imageOffset - 44;
+ sprite->has_palette = (sprite->palettesize > 0);
+
+ /* sprite has no mask if imageOffset == maskOffset */
+ if (imageOffset == maskOffset) {
+ sprite->has_mask = false;
+ header->image_size = nextSpriteOffset - 44 - sprite->palettesize;
+ header->mask_size = 0;
+ } else {
+ sprite->has_mask = true;
+ header->image_size = maskOffset - imageOffset;
+ header->mask_size = nextSpriteOffset - 44 - sprite->palettesize - header->image_size;
+ }
+
+ if (sprite->has_palette) {
+ uint32_t j, word1, word2, entry;
+ assert(sprite->palettesize % 8 == 0);
+ sprite->palette = malloc(sizeof(uint32_t) * sprite->palettesize);
+ paletteEntries = sprite->palettesize / 8;
+
+ /* Each palette entry is two words big
+ * The second word is a duplicate of the first
+ * I think this is in case you ever wanted flashing colours
+ * PRM1-730
+ */
+ for (j = 0; j < paletteEntries; j++) {
+ ERRCHK(rosprite_read_word(reader, ctx, &word1));
+ ERRCHK(rosprite_read_word(reader, ctx, &word2));
+ assert(word1 == word2); /* if they aren't equal, flashing colours are desired, which we don't support */
+
+ /* swap rr and bb parts -- PRM1-731 */
+ entry = ((word1 & 0xff000000) >> 16) | (word1 & 0x00ff0000) | ((word1 & 0x0000ff00) << 16) | 0xff;
+ sprite->palette[j] = entry;
+ }
+ }
+
+ image = malloc(header->image_size);
+ reader(image, header->image_size, ctx);
+
+ if (sprite->has_mask) {
+ mask = malloc(header->mask_size);
+ reader(mask, header->mask_size, ctx);
+ }
+
+ /* sanity check image_size */
+ assert((header->width_words) * 4 * (sprite->height) == header->image_size);
+ /* TODO: sanity check mask_size */
+ if (sprite->mode.colorbpp > 8) {
+ ERRCHK(rosprite_load_high_color(image, mask, sprite, header));
+ } else {
+ ERRCHK(rosprite_load_low_color(image, mask, sprite, header));
+ }
+
+ free(image);
+ free(mask);
+ free(header);
+
+ *result = sprite;
+
+ return ROSPRITE_OK;
+}
+
+/**
+ * Determine the sprite_mode for the specified sprite_mode_word.
+ *
+ * \param[out] result
+ */
+static rosprite_error rosprite_get_mode(uint32_t sprite_mode_word, struct rosprite_mode* result)
+{
+ struct rosprite_mode mode;
+
+ uint32_t spriteType = (sprite_mode_word & (15 << 27)) >> 27; /* preserve bits 27-30 only */
+
+ if (spriteType != 0) {
+ bool hasEightBitAlpha = sprite_mode_word >> 31; /* bit 31 */
+ /* new modes have 1bpp masks (PRM5a-111)
+ * unless bit 31 is set (http://select.riscos.com/prm/graphics/sprites/alphachannel.html)
+ */
+ mode.maskbpp = (hasEightBitAlpha ? 8 : 1);
+ mode.mask_width = mode.maskbpp;
+ mode.xdpi = (sprite_mode_word & (8191 << 14)) >> 14; /* preserve bits 14-26 only */
+ mode.ydpi = (sprite_mode_word & (8191 << 1)) >> 1; /* preserve bits 1-13 only */
+
+ mode.color_model = ROSPRITE_RGB;
+ switch (spriteType) {
+ case 1:
+ mode.colorbpp = 1; break;
+ case 2:
+ mode.colorbpp = 2; break;
+ case 3:
+ mode.colorbpp = 4; break;
+ case 4:
+ mode.colorbpp = 8; break;
+ case 5:
+ mode.colorbpp = 16; break;
+ case 6:
+ mode.colorbpp = 32; break;
+ case 7:
+ mode.colorbpp = 32;
+ mode.color_model = ROSPRITE_CMYK;
+ break;
+ case 8:
+ mode.colorbpp = 24; break;
+ default:
+ return ROSPRITE_BADMODE;
+ }
+ } else {
+ assert(sprite_mode_word < 256); /* don't think you can have modes over 255? */
+
+ mode = oldmodes[sprite_mode_word];
+ }
+
+ /* illegal mode check */
+ if ((mode.colorbpp == 0) || (mode.xdpi == 0) || (mode.ydpi == 0)) {
+ return ROSPRITE_BADMODE;
+ }
+
+ memcpy(result, &mode, sizeof(struct rosprite_mode));
+
+ return ROSPRITE_OK;
+}
+
+/**
+ * Load a sprite image with 16 or more bpp.
+ *
+ * \param[out] sprite On exit, sprite.image will be populated
+ */
+static rosprite_error rosprite_load_high_color(uint8_t* image_in, uint8_t* mask, struct rosprite* sprite, struct rosprite_header* header)
+{
+ struct rosprite_mask_state* mask_state = NULL;
+ uint32_t currentByteIndex = 0;
+ uint32_t j, x, y, x_pixels, pixel;
+ bool has_alpha_pixel_data = false;
+ uint8_t b;
+ bool old_has_alpha;
+
+ if (sprite->has_mask) {
+ ERRCHK(rosprite_init_mask_state(sprite, header, mask, &mask_state));
+ }
+
+ sprite->image = malloc(sprite->width * sprite->height * 4); /* all image data is 32bpp going out */
+
+ /* Spec says that there must be no left-hand wastage */
+ assert(header->first_used_bit == 0);
+
+ {
+ const uint32_t bpp = sprite->mode.colorbpp;
+ const uint32_t bytesPerPixel = bpp / 8;
+ const uint32_t row_max_bit = header->width_words * 32 - (31 - header->last_used_bit); /* Last used bit in row */
+
+ for (y = 0; y < sprite->height; y++) {
+ x_pixels = 0;
+ for (x = 0; x < row_max_bit; x += bpp) {
+ pixel = 0;
+ for (j = 0; j < bytesPerPixel; j++) {
+ b = image_in[currentByteIndex++];
+ pixel = pixel | (b << (j * 8));
+ }
+
+ old_has_alpha = has_alpha_pixel_data;
+ pixel = rosprite_upscale_color(pixel, &(sprite->mode), &has_alpha_pixel_data);
+ if (old_has_alpha != has_alpha_pixel_data && (y > 0 || x_pixels > 0)) {
+ rosprite_fix_alpha(sprite->image, (y * sprite->width) + x_pixels - 1);
+ }
+ if (sprite->has_mask) {
+ uint8_t mask_pixel = rosprite_next_mask_pixel(mask, mask_state);
+ pixel = (pixel & 0xffffff00) | mask_pixel;
+ }
+ sprite->image[y*sprite->width + x_pixels] = pixel;
+ x_pixels++;
+ }
+
+ /* Ensure byte index is pointing at start of next row */
+ if (y + 1 < sprite->height) {
+ currentByteIndex = (currentByteIndex + 3) & ~3; /* Round up to next multiple of 4 */
+ }
+ }
+ }
+ if (sprite->has_mask) free(mask_state);
+ return ROSPRITE_OK;
+}
+
+/**
+ * Iterate over the specified number of pixels, starting at the image pointer,
+ * and set the alpha channel to 0x00.
+ */
+static inline void rosprite_fix_alpha(uint32_t* image, unsigned long pixels)
+{
+ uint32_t i;
+ for (i = 0; i <= pixels; i++) {
+ image[i] = image[i] & 0xffffff00;
+ }
+}
+
+/**
+ * Load a sprite image with 8 or fewer bpp.
+ *
+ * \param[out] sprite On exit, sprite.image will be populated
+ */
+static rosprite_error rosprite_load_low_color(uint8_t* image_in, uint8_t* mask, struct rosprite* sprite, struct rosprite_header* header)
+{
+ uint32_t current_byte_index, currentword;
+ uint32_t x, y, x_pixels, pixel;
+ uint8_t mask_pixel;
+
+ struct rosprite_mask_state* mask_state = NULL;
+ if (sprite->has_mask) {
+ ERRCHK(rosprite_init_mask_state(sprite, header, mask, &mask_state));
+ }
+
+ sprite->image = malloc(sprite->width * sprite->height * 4); /* all image data is 32bpp going out */
+
+ {
+ const uint32_t bpp = sprite->mode.colorbpp;
+ const uint32_t row_max_bit = header->width_words * 32 - (31 - header->last_used_bit); /* Last used bit in row */
+ const uint32_t bitmask = (1 << bpp) - 1; /* creates a mask of 1s that is bpp bits wide */
+
+ current_byte_index = 0;
+ currentword = BTUINT((image_in + current_byte_index));
+ current_byte_index += 4;
+
+ for (y = 0; y < sprite->height; y++) {
+ x_pixels = 0;
+ for (x = header->first_used_bit; x < row_max_bit ; x += bpp) {
+ const uint32_t offset_into_word = x % 32;
+
+ pixel = (currentword & (bitmask << offset_into_word)) >> offset_into_word;
+ pixel = rosprite_palette_lookup(sprite, pixel); /* lookup returns 32bpp */
+ if (sprite->has_mask) {
+ mask_pixel = rosprite_next_mask_pixel(mask, mask_state);
+ pixel = (pixel & 0xffffff00) | mask_pixel;
+ }
+ sprite->image[y*sprite->width + x_pixels] = pixel;
+ x_pixels++;
+
+ /* If we're not at the end of the row and we've processed all of this word, fetch the next one */
+ if (x + bpp < row_max_bit && offset_into_word + bpp == 32) {
+ currentword = BTUINT((image_in + current_byte_index));
+ current_byte_index += 4;
+ }
+ }
+
+ /* Advance to first word of next row */
+ if (y + 1 < sprite->height) {
+ currentword = BTUINT((image_in + current_byte_index));
+ current_byte_index += 4;
+ }
+ }
+ }
+ if (sprite->has_mask) free(mask_state);
+
+ return ROSPRITE_OK;
+}
+
+static uint32_t rosprite_palette_lookup(struct rosprite* sprite, uint32_t pixel)
+{
+ uint32_t translated_pixel;
+ /* because we're dealing with 8bpp or less */
+ if (sprite->has_palette) {
+
+ if(pixel < (sprite->palettesize / 8)) {
+ translated_pixel = sprite->palette[pixel];
+ } else {
+ translated_pixel = sprite_8bpp_palette[pixel];
+ }
+ } else {
+ switch (sprite->mode.colorbpp) {
+ case 8:
+ assert(pixel < 256);
+ translated_pixel = sprite_8bpp_palette[pixel];
+ break;
+ case 4:
+ assert(pixel < 16);
+ translated_pixel = sprite_4bpp_palette[pixel];
+ break;
+ case 2:
+ assert(pixel < 4);
+ translated_pixel = sprite_2bpp_palette[pixel];
+ break;
+ case 1:
+ assert(pixel < 2);
+ translated_pixel = sprite_1bpp_palette[pixel];
+ break;
+ default:
+ translated_pixel = 0;
+ assert(false);
+ }
+ }
+ return translated_pixel;
+}
+
+static rosprite_error rosprite_init_mask_state(struct rosprite* sprite, struct rosprite_header* header, uint8_t* mask, struct rosprite_mask_state** result)
+{
+ struct rosprite_mask_state* mask_state = malloc(sizeof(struct rosprite_mask_state));
+ if (!mask_state) return ROSPRITE_NOMEM;
+
+ mask_state->x = header->first_used_bit;
+ mask_state->y = 0;
+ mask_state->first_used_bit = header->first_used_bit;
+ mask_state->row_max_bit = sprite->width * sprite->mode.mask_width;
+ mask_state->height = sprite->height;
+ mask_state->bpp = sprite->mode.mask_width;
+ mask_state->current_word = BTUINT(mask);
+ mask_state->current_byte_index = 4;
+
+ *result = mask_state;
+
+ return ROSPRITE_OK;
+}
+
+/**
+ * Get the next mask byte.
+ * A mask of 0xff denotes 100% opaque, 0x00 denotes 100% transparent.
+ *
+ * \param[in,out] mask_state
+ */
+static uint32_t rosprite_next_mask_pixel(uint8_t* mask, struct rosprite_mask_state* mask_state)
+{
+ /* a 1bpp mask (for new mode sprites), each row is word aligned (therefore potential righthand wastage */
+ const uint32_t bitmask = (1 << mask_state->bpp) - 1;
+ const uint32_t offset_into_word = mask_state->x % 32;
+ uint32_t pixel = (mask_state->current_word & (bitmask << offset_into_word)) >> offset_into_word;
+
+ if (mask_state->x + mask_state->bpp < mask_state->row_max_bit && offset_into_word + mask_state->bpp == 32) {
+ mask_state->current_word = BTUINT((mask + mask_state->current_byte_index));
+ mask_state->current_byte_index += 4;
+ }
+
+ mask_state->x += mask_state->bpp;
+ if (mask_state->x >= mask_state->row_max_bit) {
+ mask_state->x = mask_state->first_used_bit;
+
+ if (mask_state->y + 1 < mask_state->height) {
+ mask_state->current_word = BTUINT((mask + mask_state->current_byte_index));
+ mask_state->current_byte_index += 4;
+ }
+
+ mask_state->y++;
+ }
+
+ /*
+ * if the mask is 1bpp, make sure the whole byte is 0x00 or 0xff
+ */
+ if (mask_state->bpp < 8) {
+ pixel = (pixel & 1) ? 0xff : 0x00;
+ }
+
+ return pixel;
+}
+
+/**
+ * Upscale a 16, 24 or 32bpp sprite to the 0xRRGGBBAA representation.
+ * Do not call this function with a sprite with less than 16bpp,
+ * but use a palette lookup instead.
+ */
+static uint32_t rosprite_upscale_color(uint32_t pixel, struct rosprite_mode* mode, bool* has_alpha_pixel_data)
+{
+ uint8_t alpha;
+ switch (mode->colorbpp) {
+ case 32:
+ if (mode->color_model == ROSPRITE_RGB) {
+ /* swap from 0xAABBGGRR to 0xRRGGBBAA */
+ pixel = BSWAP(pixel);
+ } else {
+ pixel = rosprite_cmyk_to_rgb(pixel);
+ }
+ break;
+ case 24:
+ /* reverse byte order */
+ pixel = BSWAP(pixel);
+ break;
+ case 16:
+ /* incoming format is b_00000000000000000bbbbbgggggrrrrr */
+ {
+ uint8_t red = pixel & 31;
+ uint8_t green = (pixel & (31 << 5)) >> 5;
+ uint8_t blue = (pixel & (31 << 10)) >> 10;
+
+ /* sanity check */
+ assert(red < 32);
+ assert(green < 32);
+ assert(blue < 32);
+
+ pixel = (sprite_16bpp_translate[red] << 24)
+ | (sprite_16bpp_translate[green] << 16)
+ | (sprite_16bpp_translate[blue] << 8);
+ }
+ break;
+ case 8:
+ case 4:
+ case 2:
+ case 1:
+ assert(false); /* shouldn't need to call for <= 8bpp, since a palette lookup will return 32bpp */
+ default:
+ assert(false); /* unknown bpp */
+ }
+
+ alpha = pixel & 0xff;
+ if (alpha == 0x00) {
+ if (!(*has_alpha_pixel_data)) {
+ pixel = pixel | 0xff;
+ }
+ } else {
+ *has_alpha_pixel_data = true;
+ }
+ return pixel;
+}
+
+static inline uint32_t rosprite_cmyk_to_rgb(uint32_t cmyk)
+{
+ uint8_t c = cmyk & 0xff;
+ uint8_t m = (cmyk & 0xff00) >> 8;
+ uint8_t y = (cmyk & 0xff0000) >> 16;
+ uint8_t k = cmyk >> 24;
+
+ /* Convert to CMY colourspace */
+ uint8_t C = c + k;
+ uint8_t M = m + k;
+ uint8_t Y = y + k;
+
+ /* And to RGB */
+ uint8_t r = 255 - C;
+ uint8_t g = 255 - M;
+ uint8_t b = 255 - Y;
+
+ return r << 24 | g << 16 | b << 8;
+}
+
+static inline rosprite_error rosprite_read_word(reader reader, void* ctx, uint32_t* result)
+{
+ unsigned char b[4];
+ if (reader(b, 4, ctx) < 4) {
+ return ROSPRITE_EOF;
+ }
+ *result = BTUINT(b);
+ return ROSPRITE_OK;
+}