/* * Raycaster, based on lodev engine tutorial * Plan: * - Improve collision detection: * - During movement function, * - Check if new pos has distance from possible wall hor and ver * - Make rendering variables global with prefix * - Convert rendering function to assembly * - Add sprites (as this is done after walls) */ #define word char #include "lib/math.c" #include "lib/stdlib.c" #include "lib/sys.c" #include "lib/gfx.c" #include "lib/fp.c" // Note: these are also hardcoded in the render assembly, so update there as well! #define FB_ADDR 0xD00000 #define screenWidth 160 #define screenHeight 120 #define texWidth 64 #define texHeight 64 #define mapWidth 24 #define mapHeight 24 // Input #define BTN_LEFT 256 #define BTN_RIGHT 257 #define BTN_UP 258 #define BTN_DOWN 259 // Colors #define COLOR_RED 224 #define COLOR_DARK_RED 96 #define COLOR_GREEN 28 #define COLOR_DARK_GREEN 12 #define COLOR_BLUE 3 #define COLOR_DARK_BLUE 2 #define COLOR_WHITE 0xFF #define COLOR_GREY 0xB6 #define COLOR_YELLOW 0xFC #define COLOR_DARK_YELLOW 0x90 // Data /* - LUTdirX - LUTdirY - LUTplaneX - LUTplaney - texture */ #include "data/raydat.c" // Framebuffer. fb[Y][X] (bottom right is [239][319]) char (*fb)[320] = (char (*)[320])FB_ADDR; word worldMap[mapWidth][mapHeight] = { {4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 7, 7, 7, 7, 7, 7, 7, 7}, {4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 7}, {4, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7}, {4, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7}, {4, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 7}, {4, 0, 4, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 7, 7, 0, 7, 7, 7, 7, 7}, {4, 0, 5, 0, 0, 0, 0, 2, 0, 1, 0, 1, 0, 1, 0, 2, 7, 0, 0, 0, 7, 7, 7, 1}, {4, 0, 6, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 2, 7, 0, 0, 0, 0, 0, 0, 8}, {4, 0, 7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 7, 7, 1}, {4, 0, 8, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 5, 7, 0, 0, 0, 0, 0, 0, 8}, {4, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 5, 7, 0, 0, 0, 7, 7, 7, 1}, {4, 0, 0, 0, 0, 0, 0, 5, 5, 5, 5, 0, 5, 5, 5, 5, 7, 7, 7, 7, 7, 7, 7, 1}, {6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 0, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6}, {8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4}, {6, 6, 6, 6, 6, 6, 0, 6, 6, 6, 6, 0, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6}, {4, 4, 4, 4, 4, 4, 0, 4, 4, 4, 6, 0, 6, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3}, {4, 0, 0, 0, 0, 0, 0, 0, 0, 4, 6, 0, 6, 2, 0, 0, 0, 0, 0, 2, 0, 0, 0, 2}, {4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 2, 0, 0, 5, 0, 0, 2, 0, 0, 0, 2}, {4, 0, 0, 0, 0, 0, 0, 0, 0, 4, 6, 0, 6, 2, 0, 0, 0, 0, 0, 2, 2, 0, 2, 2}, {4, 0, 6, 0, 6, 0, 0, 0, 0, 4, 6, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 2}, {4, 0, 0, 5, 0, 0, 0, 0, 0, 4, 6, 0, 6, 2, 0, 0, 0, 0, 0, 2, 2, 0, 2, 2}, {4, 0, 6, 0, 6, 0, 0, 0, 0, 4, 6, 0, 6, 2, 0, 0, 5, 0, 0, 2, 0, 0, 0, 2}, {4, 0, 0, 0, 0, 0, 0, 0, 0, 4, 6, 0, 6, 2, 0, 0, 0, 0, 0, 2, 0, 0, 0, 2}, {4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3}}; word frameDone = 0; // Global render variables word drawStart = 0; word drawEnd = 0; word texNum = 0; word side = 0; // was a NorthSouth or a EastWest wall hit? // x and y start position fixed_point_t RAY_posX; fixed_point_t RAY_posY; // initial direction vector fixed_point_t RAY_dirX; fixed_point_t RAY_dirY; // the 2d raycaster version of camera plane fixed_point_t RAY_planeX; fixed_point_t RAY_planeY; // Render entire screen // Registers (global): // r1 x current vertical line (x of screen) void RAYFX_renderScreen() { // reg 4 5 6 7 (args) and 2 3 (retval) are safe asm( // backdup registers "push r1\n" "push r8\n" "push r9\n" "push r10\n" "push r11\n" "push r12\n" "push r13\n" "push r14\n" "push r15\n" ); asm( // r1: current vertical line (x of screen) "load32 0 r1\n" // for each vertical line (x) "RAYFX_screenXloop:\n" // cameraX "addr2reg LUTcameraX r15\n" // r15 = LUTcameraX "add r15 r1 r15\n" // r15 = LUTcameraX[x] addr "read 0 r15 r15\n" // r15 = LUTcameraX[x] value // r2 rayDirx [FP] x dir of ray // r3 rayDiry [FP] y dir of ray // r2: rayDirX "addr2reg RAY_dirX r14\n" // r14 = RAY_dirX addr "read 0 r14 r14\n" // r14 = RAY_dirX value "addr2reg RAY_planeX r13\n" // r13 = RAY_planeX addr "read 0 r13 r13\n" // r13 = RAY_planeX value "multfp r13 r15 r2\n" // r2 = FP_Mult(RAY_planeX, cameraX) "add r2 r14 r2\n" // r2 += RAY_dirX // r3: rayDirY "addr2reg RAY_dirY r14\n" // r14 = RAY_dirY addr "read 0 r14 r14\n" // r14 = RAY_dirY value "addr2reg RAY_planeY r13\n" // r13 = RAY_planeY addr "read 0 r13 r13\n" // r13 = RAY_planeY value "multfp r13 r15 r3\n" // r3 = FP_Mult(RAY_planeY, cameraX) "add r3 r14 r3\n" // r3 += RAY_dirY // r4: deltaDistX "load32 1 r15\n" // r15 = 1 "shiftl r15 16 r15\n" // r15 = FP(1) "load32 0xC02742 r14\n" // r14 = addr fpdiv_writea "write 0 r14 r15\n" // write a (fp1) to divider "write 1 r14 r2\n" // write b (rayDirX) to divider and perform division "read 1 r14 r4\n" // read result to r4 "shiftrs r4 31 r13\n" // r13 = y = x >>(signed) 31 (start of abs) "xor r4 r13 r4\n" // r4 = (x ^ y) "sub r4 r13 r4\n" // r4 -= y (result of abs) // r5: deltaDistY (uses r14 and r15 from above) "write 0 r14 r15\n" // write a (fp1) to divider "write 1 r14 r3\n" // write b (rayDirY) to divider and perform division "read 1 r14 r5\n" // read result to r5 "shiftrs r5 31 r13\n" // r13 = y = x >>(signed) 31 (start of abs) "xor r5 r13 r5\n" // r5 = (x ^ y) "sub r5 r13 r5\n" // r5 -= y (result of abs) // if (rayDirX < 0), else // r6: stepX // r7: stepY // r8: sideDistX // r9: sideDistY // r10: mapX // r11: mapY "blts r2 r0 2\n" // if (rayDirX < 0) skip next line "jump RAYFX_rayDirXge0\n" // goto RAYFX_rayDirXge0 "load32 -1 r6\n" // r6 = stepX = -1 "addr2reg RAY_posX r15\n" // r15 = RAY_posX addr "read 0 r15 r15\n" // r15 = RAY_posX value "shiftrs r15 16 r10\n" // mapX = int(RAY_posX) "load32 0xFFFF r14\n" // r14 = decimal part mask "and r15 r14 r15\n" // r15 = RAY_posX decimal part "multfp r15 r4 r8\n" // sideDistX = RAY_posX decimal part * deltaDistX "jump RAYFX_rayDirXltEnd\n" // skip the else part "RAYFX_rayDirXge0:\n" "load32 1 r6\n" // stepX = 1 "addr2reg RAY_posX r15\n" // r15 = RAY_posX addr "read 0 r15 r15\n" // r15 = RAY_posX value "shiftrs r15 16 r10\n" // r10 (mapX) = r15 >> 16 (to int) "add r10 1 r14\n" // r14 = int(RAY_posX) + 1 "shiftl r14 16 r14\n" // r14 <<=16 (to FP) "sub r14 r15 r15\n" // r15 = r14 - RAY_posX "multfp r15 r4 r8\n" // sideDistX = RAY_posX-ish * deltaDistX "RAYFX_rayDirXltEnd:\n" // if (rayDirY < 0), else "blts r3 r0 2\n" // if (rayDirY < 0) skip next line "jump RAYFX_rayDirYge0\n" // goto RAYFX_rayDirYge0 "load32 -1 r7\n" // r7 = stepY = -1 "addr2reg RAY_posY r15\n" // r15 = RAY_posY addr "read 0 r15 r15\n" // r15 = RAY_posY value "shiftrs r15 16 r11\n" // mapY = int(RAY_posY) "load32 0xFFFF r14\n" // r14 = decimal part mask "and r15 r14 r15\n" // r15 = RAY_posY decimal part "multfp r15 r5 r9\n" // sideDistY = RAY_posY decimal part * deltaDistY "jump RAYFX_rayDirYltEnd\n" // skip the else part "RAYFX_rayDirYge0:\n" "load32 1 r7\n" // stepY = 1 "addr2reg RAY_posY r15\n" // r15 = RAY_posY addr "read 0 r15 r15\n" // r15 = RAY_posY value "shiftrs r15 16 r11\n" // r11 (mapY) = r15 >> 16 (to int) "add r11 1 r14\n" // r14 = int(RAY_posY) + 1 "shiftl r14 16 r14\n" // r14 <<=16 (to FP) "sub r14 r15 r15\n" // r15 = r14 - RAY_posX "multfp r15 r5 r9\n" // sideDistY = RAY_posX-ish * deltaDistY "RAYFX_rayDirYltEnd:\n" // DDA (uses tmp r15) "load32 0 r15\n" // hit = 0 "RAYFX_DDAwhileNoHit:\n" // while (hit == 0) "beq r15 r0 2\n" // while check "jump RAYFX_DDAwhileNoHitDone\n" // if (sideDistX < sideDistY), else "blts r8 r9 2\n" // if (sideDistX < sideDistY) skip next line "jump RAYFX_sideDistXltY\n" // goto RAYFX_sideDistXltY "add r8 r4 r8\n" // sideDistX += deltaDistX; "add r10 r6 r10\n" // mapX += stepX; "addr2reg side r14\n" // side; "write 0 r14 r0\n" // side = 0; "jump RAYFX_sideDistXltYend\n" // skip the else part "RAYFX_sideDistXltY:\n" "add r9 r5 r9\n" // sideDistY += deltaDistY; "add r11 r7 r11\n" // mapY += stepY; "addr2reg side r14\n" // side; "load32 1 r13\n" // 1 "write 0 r14 r13\n" // side = 1; "RAYFX_sideDistXltYend:\n" "addr2reg worldMap r14\n" // r14 = worldMap addr; "multu r10 24 r13\n" // r13 = mapX offset using mapHeight "add r13 r11 r13\n" // r13 += mapY offset "add r13 r14 r14\n" // r14 = worldMap[mapX][mapY] addr "read 0 r14 r14\n" // r14 = worldMap[mapX][mapY] value "bles r14 r0 2\n" // skip next instruction if worldMap[mapX][mapY] <= 0 "load 1 r15\n" // hit = 1 "jump RAYFX_DDAwhileNoHit\n" // return to while loop start "RAYFX_DDAwhileNoHitDone:\n" // From this point, r10 r11 mapx mapy (and r15) are free // texNum = worldMap[mapX][mapY] - 1; // assumes worldMap[mapX][mapY] value is still in r14 "addr2reg texNum r13\n" // r13 = texNum addr; "sub r14 1 r14\n" // r14 = worldMap[mapX][mapY] - 1 "write 0 r13 r14\n" // write texNum; // r10: perpWallDist (FP) "addr2reg side r15\n" // side addr "read 0 r15 r15\n" // side value // if (side == 0), else "bne r15 r0 3\n" // if (side != 0) skip next two lines "sub r8 r4 r10\n" // perpWallDist = (sideDistX - deltaDistX); (match) "jumpo 2\n" // skip else part "sub r9 r5 r10\n" // perpWallDist = (sideDistY - deltaDistY); (else) // From this point sideDistX&Y and deltaDistX&Y are free // this frees up regs 4 5 8 and 9 // leaving to use: 4, 5, 8, 9, 11, 12, 13, 14, 15 // r4: lineHeight "load32 120 r15\n" // r15 = screenHeight "shiftl r15 16 r15\n" // r15 = FP(screenHeight) "load32 0xC02742 r14\n" // r14 = addr fpdiv_writea "write 0 r14 r15\n" // write a (FP(screenHeight) to divider "write 1 r14 r10\n" // write b (perpWallDist) to divider and perform division "read 1 r14 r4\n" // read result to r4 "shiftrs r4 16 r4\n" // r4 = lineHeight = int(r4) "shiftrs r4 1 r15\n" // r15 = lineHeight >> 1 "load32 -1 r14\n" // r14 = -1 "mults r15 r14 r15\n" // r15 = -r15 "load32 60 r14\n" // r14 = screenHeight >> 1 "add r14 r15 r15\n" // r15 = drawStart value (r14+r15) "bges r15 r0 2\n" // skip next line if drawStart >= 0 "load 0 r15\n" // set drawStart to 0 if < 0 "addr2reg drawStart r14\n" // r14 = drawStart addr "write 0 r14 r15\n" // write drawStart value // skip render if start > 118 "load32 118 r14\n" "blts r15 r14 2 \n" "jump RAYFX_skipRenderLine\n" "shiftrs r4 1 r15\n" // r15 = lineHeight >> 1 "load32 60 r14\n" // r14 = screenHeight >> 1 "add r14 r15 r15\n" // r15 = drawEnd value (r14+r15) "load32 120 r14\n" // r14 = screenHeight "blts r15 r14 2\n" // skip next line if drawEnd < screenHeight "load 120 r15\n" // set drawEnd to screenHeight - 1 "addr2reg drawEnd r14\n" // r14 = drawEnd addr "write 0 r14 r15\n" // write drawEnd value // texture calculations // r8: side // r5: wallX "addr2reg side r8\n" // r8 = side addr "read 0 r8 r8\n" // r8 = side value "bne r8 r0 7\n" // if side != 0, goto else part (addr2reg is two instructions!) "addr2reg RAY_posY r15\n" // r15 = RAY_posY addr "read 0 r15 r15\n" // r15 = RAY_posY value "multfp r10 r3 r14\n" // r14 = perpWallDist * rayDirY "add r14 r15 r5\n" // r5 = wallX = r14 + RAY_posY "jumpo 5\n" // skip else // else "addr2reg RAY_posX r15\n" // r15 = RAY_posX addr "read 0 r15 r15\n" // r15 = RAY_posX value "multfp r10 r2 r14\n" // r14 = perpWallDist, rayDirX "add r14 r15 r5\n" // r5 = wallX = r14 + RAY_posX "load32 0xFFFF r15\n" // r15 = floormask "and r5 r15 r5\n" // wallX-=floor(wallX) // r6: texX "load32 64 r15\n" // r15 = texWidth "shiftl r15 16 r14\n" // r14 = FP(texWidth) "multfp r14 r5 r6\n" // r6 = FP_Mult(wallX, FP_intToFP(texWidth)) "shiftrs r6 16 r6\n" // r6 = int(r6) "bne r8 r0 4\n" // skip if side != 0 "bles r2 r0 3\n" // skip if rayDirX <= 0 "sub r15 r6 r6\n" // texX = texWidth - texX "sub r6 1 r6\n" // texX -= 1 "beq r8 r0 4\n" // skip if side == 0 "bges r3 r0 3\n" // skip if rayDirY >= 0 "sub r15 r6 r6\n" // texX = texWidth - texX "sub r6 1 r6\n" // texX -= 1 // r2 and r3 are free now (no rayDirX&Y needed) // r5: step "load32 64 r15\n" // r15 = texHeight "shiftl r15 16 r15\n" // r15 = FP(texHeight) "shiftl r4 16 r14\n" // r14 = FP(lineHeight) "load32 0xC02742 r13\n" // r13 = addr fpdiv_writea "write 0 r13 r15\n" // write a (FP(texHeight) to divider "write 1 r13 r14\n" // write b (FP(lineHeight)) to divider and perform division "read 1 r13 r5\n" // read result to r5 // r4: texPos "addr2reg drawStart r15\n" // r15 = drawStart addr "read 0 r15 r15\n" // r15 = drawStart value "sub r15 60 r15\n" // r15 -= (screenHeight >> 1) "shiftrs r4 1 r14\n" // r14 = lineHeight >> 1 "add r15 r14 r15\n" // r15 += lineHeight >> 1 "shiftl r15 16 r15\n" // r15 = FP(r15) "multfp r15 r5 r4\n" // r4 = r15 * step "shiftl r1 0 r7\n" // move x to r7 // Render vertical line in pixel plane with textures // Registers: // r1 first pixel addr VRAM addr of first pixel in line (top pixel) // r2 (a2r) drawStart Starting pixel of wall // r3 (a2r) drawEnd Ending pixel of wall // r4 texPos Starting texture coordinate // r5 step How much to increase the texture coordinate per screen pixel // r6 texX X coordinate on the texture // r7 x X position of line to render // r8 current FB pos Current framebuffer position in VRAM (top to bottom) // r9 end loop FB pos Last framebuffer position in VRAM of current loop // r10 texY Y coordinate on the texture // r11 gp Used as temp reg in calculations // r12 texture[texNum] Texture array of texture to draw // r13 color Pixel color // r14 ceil or floor col Ceiling or floor color // r15 side North South or East West wall side "push r1\n" // backup x loop var "addr2reg drawStart r2 ; r2 = drawStart addr\n" "read 0 r2 r2 ; r2 = drawStart value\n" "addr2reg drawEnd r3 ; r3 = drawEnd addr\n" "read 0 r3 r3 ; r3 = drawEnd value\n" "load32 0xD00000 r1 ; r1 = framebuffer addr\n" "add r1 r7 r1 ; r1 = first pixel in line (fb+x)\n" "or r0 r1 r8 ; r8 = current pixel\n" "multu r2 320 r9 ; r9 = drawStart VRAM offset\n" "add r9 r1 r9 ; r9 = last FB pos of before wall\n" "addr2reg texNum r12 ; r12 = texNum addr\n" "read 0 r12 r12 ; r12 = texNum value\n" "multu r12 4096 r12 ; r12 = texture offset (64*64 per texture)\n" "addr2reg texture r11 ; r11 = texture array\n" "add r12 r11 r12 ; r12 = texture[texNum]\n" "load32 0x0082F0 r14 ; r14 = ceiling color\n" "addr2reg side r15 ; r15 = side addr\n" "read 0 r15 r15 ; r15 = side value\n" "ble r2 r0 5 ; skip ceiling if wall starts at first pixel\n" // draw until start "RAYFX_drawVlineLoopCeiling:\n" " write 0 r8 r14 ; write ceiling pixel\n" " add r8 320 r8 ; go to next line pixel\n" " bge r8 r9 2 ; keep looping until reached wall\n" " jump RAYFX_drawVlineLoopCeiling\n" "multu r3 320 r9 ; r9 = drawEnd VRAM offset\n" "add r9 r1 r9 ; r9 = last FB pos of wall\n" "load32 8355711 r2 ; r2 = mask for darken color\n" // draw until floor "RAYFX_drawVlineLoopWall:\n" " shiftrs r4 16 r11 ; r11 = texY = FPtoInt(texPos)\n" " and r11 63 r11 ; r11 = r11 & (texHeight-1)\n" " add r4 r5 r4 ; texPos += step\n" " multu r11 64 r11 ; r11 = texHeight * texY \n" " add r11 r6 r11 ; r11 += texX\n" " add r11 r12 r13 ; r13 = addr of color in texture array\n" " read 0 r13 r13 ; r13 = pixel color\n" " beq r15 r0 3 ; skip next two lines if not side of wall is hit\n" " shiftrs r13 1 r13\n" // r13 >> 1 " and r13 r2 r13 ; r13 & darken color mask\n" " write 0 r8 r13 ; write texture pixel\n" " add r8 320 r8 ; go to next line pixel\n" " bge r8 r9 2 ; keep looping until reached floor\n" " jump RAYFX_drawVlineLoopWall\n" "load32 120 r11\n" "bge r3 r11 10 ; skip floor if wall ends at bottom of screen\n" "load32 119 r9 ; r9 = last y position\n" "multu r9 320 r9 ; r9 = screen end VRAM offset\n" "add r9 r1 r9 ; r9 = last FB pos of line\n" "load32 0x9E9E9E r14 ; r14 = floor color\n" "; draw until end of screen\n" "RAYFX_drawVlineLoopFloor:\n" " write 0 r8 r14 ; write floor pixel\n" " add r8 320 r8 ; go to next line pixel\n" " bgt r8 r9 2 ; keep looping until reached end of screen\n" " jump RAYFX_drawVlineLoopFloor\n" "pop r1\n" // restore x loop var "RAYFX_skipRenderLine:\n" "add r1 1 r1\n" // r1 = x++ "load32 160 r15\n" // r15 = stop x loop (screenWidth) "bge r1 r15 2\n" // keep looping until reached final vline (x) of screen "jump RAYFX_screenXloop\n" ); asm( // restore registers "pop r15\n" "pop r14\n" "pop r13\n" "pop r12\n" "pop r11\n" "pop r10\n" "pop r9\n" "pop r8\n" "pop r1\n" ); } int main() { // clear screen from text GFX_clearWindowtileTable(); GFX_clearWindowpaletteTable(); GFX_clearBGtileTable(); GFX_clearBGpaletteTable(); GFX_setHalfRes(1); // x and y start position RAY_posX = FP_intToFP(15); RAY_posY = FP_StringToFP("11.5"); // initial direction vector RAY_dirX = LUTdirX[0]; RAY_dirY = LUTdirY[0]; // the 2d raycaster version of camera plane RAY_planeX = LUTplaneX[0]; RAY_planeY = LUTplaneY[0]; // rotation angle (loops at 360) word rotationAngle = 0; word rotationSpeed = 0; // degrees per frame fixed_point_t moveSpeed = 0; fixed_point_t movePadding = FP_StringToFP("0.15"); word quitGame = 0; word prevMillis = millis(); while (!quitGame) { // wait until at least one frame has passed while (!frameDone); frameDone = 0; // render screen RAYFX_renderScreen(); // calculate and draw FPS word currentMillis = millis(); word renderMillis = currentMillis - prevMillis; prevMillis = currentMillis; word fps = FP_FPtoInt(FP_Div(FP_intToFP(1000), FP_intToFP(renderMillis))); char buffer[11]; itoa(fps, buffer); // clear fps digits (assumes fps <= 999) asm( "push r1\n" "load32 0xC01420 r1 ; r1 = vram addr\n" "write 0 r1 r0 ; write char to vram\n" "write 1 r1 r0 ; write char to vram\n" "write 2 r1 r0 ; write char to vram\n" "pop r1\n" ); GFX_printWindowColored(buffer, strlen(buffer), 0, 0); // adjust movement and rotation speed based on FPS moveSpeed = FP_Mult(FP_Div(FP_intToFP(renderMillis), FP_intToFP(1000)), FP_intToFP(3)); rotationSpeed = renderMillis >> 1; // check which button is held if (bdos_usbkey_held('a')) { // both camera direction and camera plane must be rotated rotationAngle -= rotationSpeed; if (rotationAngle < 0) { rotationAngle += 1440; } RAY_dirX = LUTdirX[rotationAngle]; RAY_dirY = LUTdirY[rotationAngle]; RAY_planeX = LUTplaneX[rotationAngle]; RAY_planeY = LUTplaneY[rotationAngle]; } else if (bdos_usbkey_held('d')) { // both camera direction and camera plane must be rotated rotationAngle += rotationSpeed; if (rotationAngle >= 1440) { rotationAngle -= 1440; } RAY_dirX = LUTdirX[rotationAngle]; RAY_dirY = LUTdirY[rotationAngle]; RAY_planeX = LUTplaneX[rotationAngle]; RAY_planeY = LUTplaneY[rotationAngle]; } if (bdos_usbkey_held('w')) { word worldMapX = FP_FPtoInt(RAY_posX + FP_Mult(RAY_dirX, moveSpeed + movePadding)); word worldMapY = FP_FPtoInt(RAY_posY); if (worldMap[worldMapX][worldMapY] == 0) { RAY_posX += FP_Mult(RAY_dirX, moveSpeed); } worldMapX = FP_FPtoInt(RAY_posX); worldMapY = FP_FPtoInt(RAY_posY + FP_Mult(RAY_dirY, moveSpeed + movePadding)); if (worldMap[worldMapX][worldMapY] == 0) { RAY_posY += FP_Mult(RAY_dirY, moveSpeed); } } else if (bdos_usbkey_held('s')) { word worldMapX = FP_FPtoInt(RAY_posX - FP_Mult(RAY_dirX, moveSpeed + movePadding)); word worldMapY = FP_FPtoInt(RAY_posY); if (worldMap[worldMapX][worldMapY] == 0) { RAY_posX -= FP_Mult(RAY_dirX, moveSpeed); } worldMapX = FP_FPtoInt(RAY_posX); worldMapY = FP_FPtoInt(RAY_posY - FP_Mult(RAY_dirY, moveSpeed + movePadding)); if (worldMap[worldMapX][worldMapY] == 0) { RAY_posY -= FP_Mult(RAY_dirY, moveSpeed); } } else if (bdos_usbkey_held('e')) { word worldMapX = FP_FPtoInt(RAY_posX + FP_Mult(RAY_planeX, moveSpeed + movePadding)); word worldMapY = FP_FPtoInt(RAY_posY); if (worldMap[worldMapX][worldMapY] == 0) { RAY_posX += FP_Mult(RAY_planeX, moveSpeed); } worldMapX = FP_FPtoInt(RAY_posX); worldMapY = FP_FPtoInt(RAY_posY + FP_Mult(RAY_planeY, moveSpeed + movePadding)); if (worldMap[worldMapX][worldMapY] == 0) { RAY_posY += FP_Mult(RAY_planeY, moveSpeed); } } else if (bdos_usbkey_held('q')) { word worldMapX = FP_FPtoInt(RAY_posX - FP_Mult(RAY_planeX, moveSpeed + movePadding)); word worldMapY = FP_FPtoInt(RAY_posY); if (worldMap[worldMapX][worldMapY] == 0) { RAY_posX -= FP_Mult(RAY_planeX, moveSpeed); } worldMapX = FP_FPtoInt(RAY_posX); worldMapY = FP_FPtoInt(RAY_posY - FP_Mult(RAY_planeY, moveSpeed + movePadding)); if (worldMap[worldMapX][worldMapY] == 0) { RAY_posY -= FP_Mult(RAY_planeY, moveSpeed); } } if (hid_checkfifo()) { word c = hid_fiforead(); if (c == 27) // escape { // clean up and exit GFX_clearPXframebuffer(); GFX_clearWindowtileTable(); GFX_clearWindowpaletteTable(); GFX_clearBGtileTable(); GFX_clearBGpaletteTable(); GFX_setHalfRes(0); quitGame = 1; } else if (c == '1') { GFX_setHalfRes(0); } else if (c == '2') { GFX_setHalfRes(1); } } } return 'q'; } void interrupt() { // Handle all interrupts word i = get_int_id(); switch (i) { case INTID_TIMER1: timer1Value = 1; // Notify ending of timer1 break; case INTID_GPU: frameDone++; break; } }