// Load a BS file from CD, decompress and display it. // Schnappy 07-2021 #include #include #include #include #include // CD library #include // CODEC library #include #include #define VMODE 0 // Video Mode : 0 : NTSC, 1: PAL #define SCREENXRES 320 // Screen width #define SCREENYRES 240 + (VMODE << 4) // Screen height : If VMODE is 0 = 240, if VMODE is 1 = 256 #define CENTERX SCREENXRES/2 // Center of screen on x #define CENTERY SCREENYRES/2 // Center of screen on y #define MARGINX 8 // margins for text display #define MARGINY 16 #define FONTSIZE 8 * 7 // Text Field Height DISPENV disp[2]; // Double buffered DISPENV and DRAWENV DRAWENV draw[2]; short db = 0; // index of which buffer is used, values 0, 1 // CD specifics #define CD_SECTOR_SIZE 2048 // Converting bytes to sectors SECTOR_SIZE is defined in words, aka int #define BtoS(len) ( ( len + CD_SECTOR_SIZE - 1 ) / CD_SECTOR_SIZE ) // Name of file to load static char * loadFile; // libcd's CD file structure contains size, location and filename CdlFILE filePos = {0}; //~ struct EXEC * exeStruct; // Define start address of allocated memory // Let's use an array so we don't have to worry about using a memory segment that's already in use. static unsigned char ramAddr[0x40000]; // https://discord.com/channels/642647820683444236/663664210525290507/864936962199781387 // We could also set a memory address manually, but we have to make sure this won't get in the way of other routines. // void * ramAddr = (void *)0x80030D40; // Load data to this buffer u_long * dataBuffer; // Those are not strictly needed, but we'll use them to see the commands results. // They could be replaced by a 0 in the various functions they're used with. u_char CtrlResult[8]; // Value returned by CDread() - 1 is good, 0 is bad int CDreadOK = 0; // Value returned by CDsync() - Returns remaining sectors to load. 0 is good. int CDreadResult = 0; // BS decompression // Store size of uncompressed data long bsBufferSize; // Allocated memory address void * bsWorkBuffer; // Define image draw area RECT bsDrawArea = { 0, 0, 16, SCREENYRES}; // Used to store a 16x240 image strip u_long bsStrip[16*240]; void init(void) { ResetGraph(0); // Initialize drawing engine with a complete reset (0) SetDefDispEnv(&disp[0], 0, 0 , SCREENXRES, SCREENYRES); // Set display area for both &disp[0] and &disp[1] SetDefDispEnv(&disp[1], 0, SCREENYRES, SCREENXRES, SCREENYRES); // &disp[0] is on top of &disp[1] SetDefDrawEnv(&draw[0], 0, SCREENYRES, SCREENXRES, SCREENYRES); // Set draw for both &draw[0] and &draw[1] SetDefDrawEnv(&draw[1], 0, 0 , SCREENXRES, SCREENYRES); // &draw[0] is below &draw[1] // Set video mode if (VMODE){ SetVideoMode(MODE_PAL);} SetDispMask(1); // Display on screen setRGB0(&draw[0], 155, 0, 150); // set color for first draw area setRGB0(&draw[1], 155, 0, 150); // set color for second draw area draw[0].isbg = 0; // set mask for draw areas. 1 means repainting the area with the RGB color each frame draw[1].isbg = 0; PutDispEnv(&disp[db]); // set the disp and draw environnments PutDrawEnv(&draw[db]); FntLoad(960, 0); // Load font to vram at 960,0(+128) FntOpen(MARGINX, MARGINY, SCREENXRES - MARGINX * 2, FONTSIZE, 0, 280 ); // FntOpen(x, y, width, height, black_bg, max. nbr. chars } void display(void) { DrawSync(0); // Wait for all drawing to terminate VSync(0); // Wait for the next vertical blank PutDispEnv(&disp[db]); // set alternate disp and draw environnments PutDrawEnv(&draw[db]); db = !db; // flip db value (0 or 1) } int main(void) { // Init display init(); // Init CD system CdInit(); // Init heap InitHeap((u_long *)ramAddr, sizeof(ramAddr)); // If the other method was chosen at l.39 // InitHeap((void *)0x80030D40, 0x40000); // Set name of file to load loadFile = "\\BACE.BS;1"; // Get file position from filename CdSearchFile( &filePos, loadFile); // Allocate memory dataBuffer = malloc( BtoS(filePos.size) * CD_SECTOR_SIZE ); // Issue CdlSetloc CDROM command : Set the seek target position // Beware of a misnomed 'sector' member in the CdlLOC struct that should really be named 'frame'. // https://discord.com/channels/642647820683444236/663664210525290507/864912470996942910 CdControl(CdlSetloc, (u_char *)&filePos.pos, CtrlResult); // Read data and load it to dataBuffer CDreadOK = CdRead( (int)BtoS(filePos.size), (u_long *)dataBuffer, CdlModeSpeed ); // Wait for operation to complete CDreadResult = CdReadSync(0, 0); // Image Decompression // Initialize image processing subsystem DecDCTReset(0); // Find the needed buffer size bsBufferSize = DecDCTBufSize(dataBuffer); // Allocate buffer size at &bsWorkBuffer bsWorkBuffer = malloc( bsBufferSize ); // Decode Huffman (also called VLC: variable length coding ) compressed image DecDCTvlc( dataBuffer, (u_long *) bsWorkBuffer ); // Send decoded data to MDEC for RLE decoding. DecDCTin( (u_long*) bsWorkBuffer, 0); // Fetch decoded image in 16x240 strips for( bsDrawArea.x = 0; bsDrawArea.x < SCREENXRES; bsDrawArea.x += 16 ){ // Request decoded data from MDEC // Request 16 * 240 pixel high lines. // But size is in long words (4B), so divide by 2 to get words (2B) ? DecDCTout( bsStrip, (16*SCREENYRES)/2); // Wait for transfer to complete DecDCToutSync(0); // Load image data to fb LoadImage( &bsDrawArea, bsStrip ); } free( bsWorkBuffer ); while (1) // infinite loop { // Copy BS image to the other buffer MoveImage2(&disp[db].disp, 0, disp[!db].disp.y ); DrawSync(0); FntPrint("Hello BS! \n"); // Print filesize in bytes/sectors FntPrint("Bs Size: %dB sectors: %d\n", filePos.size, BtoS(filePos.size)); // Print heap and buffer addresses FntPrint("Heap: %x - Buf: %x\n", ramAddr, dataBuffer); FntPrint("bsWork: %x\nbsBufSize: %dB\n", bsWorkBuffer, bsBufferSize); FntFlush(-1); // Draw print stream display(); // Execute display() } return 0; }