Add first of several ray cast/rendering files

graphics/traveler/Makefile

@@ -37,16 +37,17 @@
 -include $(TOPDIR)/Make.defs
 include $(APPDIR)/Make.defs
 
-# Hello, World! built-in application info
+# Traveler built-in application info
 
 APPNAME = traveler
 PRIORITY = SCHED_PRIORITY_DEFAULT
 STACKSIZE = 2048
 
-# Hello, World! Example
+# Traveler files
 
-ASRCS =
-CSRCS = trv_color.c trv_doors.c trv_graphics.c trv_input.c trv_mem.c trv_pov.c
+ASRCS  =
+CSRCS  = trv_color.c trv_doors.c trv_graphics.c trv_input.c trv_mem.c trv_pov.c
+CSRCS += trv_rayrend.c
 MAINSRC = trv_main.c
 
 ifeq ($(CONFIG_NX),y)

graphics/traveler/include/trv_bitmaps.h

@@ -47,10 +47,54 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
+#define BITMAP_WIDTH  64
+#define BITMAP_HEIGHT 64
+#define BITMAP_LOG2H   6
+#define BITMAP_SIZE   (BITMAP_WIDTH * BITMAP_HEIGHT)
+#define BITMAP_IMASK  (BITMAP_HEIGHT-1)
+#define BITMAP_JMASK  (BITMAP_WIDTH-1)
+#define BITMAP_JSHIFT  6
+#define BMICLIP(i)    ((i) & BITMAP_IMASK)
+#define BMJCLIP(i)    ((i) & BITMAP_JMASK)
+#define BMOFFSET(i,j) (((i) << BITMAP_JSHIFT) | (j))
+#define MAX_BITMAPS   256
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/
 
+struct trv_bitmap_s
+{
+  uint16_t w;
+  uint16_t h;
+  uint8_t log2h;
+  FAR trv_pixel_t *bm;
+};
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/* These point to the (allocated) bit map buffers for the even and odd
+ * bitmaps
+ */
+
+extern struct trv_bitmap_s *g_even_bitmaps[MAX_BITMAPS];
+#ifndef WEDIT
+extern struct trv_bitmap_s *g_odd_bitmaps[MAX_BITMAPS];
+#endif
+
+/* This is the maximum value + 1 of a texture code */
+
+extern uint16_t g_trv_nbitmaps;
+
+/* These are the colors from the worldPalette which should used to rend
+ * the sky and ground
+ */
+
+extern trv_pixel_t g_sky_color;
+extern trv_pixel_t g_ground_color;
+
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/

graphics/traveler/include/trv_color.h

@@ -91,9 +91,9 @@
 
 struct trv_color_rgb_s
 {
-  uint8_t red;
-  uint8_t green;
-  uint8_t blue;
+  uint8_t red;    /* red   component of color 0-63 */
+  uint8_t green;  /* green component of color 0-63 */
+  uint8_t blue;   /* blue  component of color 0-63 */
 };
 
 struct trv_color_lum_s

graphics/traveler/include/trv_paltable.h

@@ -0,0 +1,82 @@
+/****************************************************************************
+ * apps/graphics/traveler/include/trv_paltable.h
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#ifndef __APPS_GRAPHICS_TRAVELER_INCLUDE_TRV_PALTABLE_H
+#define __APPS_GRAPHICS_TRAVELER_INCLUDE_TRV_PALTABLE_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include "trv_types.h"
+
+/****************************************************************************
+ * Pre-processor
+ ****************************************************************************/
+
+/* Here some palette-related definitions. */
+
+#define PALETTE_SIZE  256 /* This is the number of colors in the palette */
+#define NUM_ZONES      16 /* This is the number of distance zones in the palette table */
+
+/* Here are some macros used to access the palette table.  */
+
+#define PAL_SCALE_BITS     2
+#define GET_DISTANCE(x,y)  ( (x) >= (y) ? ((x) + ((y) >>1)) : ((y) + ((x) >>1)))
+#define GET_ZONE(x,y)      (GET_DISTANCE(x,y) >> (sSHIFT+PAL_SCALE_BITS))
+#define GET_PALINDEX(d)    ((d) >= NUM_ZONES ? (NUM_ZONES-1) : (d))
+#define GET_PALPTR(d)      g_paltable[GET_PALINDEX(d)]
+
+/* This is a special version which is used by the texture logic.  The
+ * texture engine used 8 bits of fraction in many of its calculation
+ */
+
+#define GET_FZONE(x,y,n)   (GET_DISTANCE(x,y) >> (sSHIFT+PAL_SCALE_BITS-(n)))
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/* This is the palette table which is used to adjust the texture values
+ * with distance
+ */
+
+extern trv_pixel_t *g_paltable[NUM_ZONES];
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#endif /* __APPS_GRAPHICS_TRAVELER_INCLUDE_TRV_PALTABLE_H */

graphics/traveler/include/trv_raycast.h

@@ -0,0 +1,166 @@
+/****************************************************************************
+ * apps/graphics/traveler/include/trv_raycast.h
+ * This is the header file associated with trv_raycast.c
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#ifndef __APPS_GRAPHICS_TRAVELER_INCLUDE_TRV_RAYCAST_H
+#define __APPS_GRAPHICS_TRAVELER_INCLUDE_TRV_RAYCAST_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include "trv_types.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* The following definitions define the world view window in terms of the
+ * 320x200 display coordinates.
+ */
+
+#define WINDOW_LEFT             0  /* Offset (in bytes) to the left side
+                                    * of the world window */
+#define WINDOW_WIDTH          320  /* Width of the world window */
+#define WINDOW_TOP              0  /* Offset (in multiples of TRV_SCREEN_WIDTH)
+                                    * to the top of world window */
+#define WINDOW_HEIGHT         200  /* height of the world window */
+#define WINDOW_MIDDLE         100  /* Center or horizon of the world window */
+
+/* This calculation tends to overflow unless it is cast carefully */
+
+#define WINDOW_SIZE (((int32_t)WINDOW_WIDTH)*((int32_t)WINDOW_HEIGHT))
+
+/* This is the biggest distance that can be represented with int16_t */
+
+#define TRV_INFINITY 0x7fff
+
+/* The actual size of the image will be determined by the
+ * both the WINDOW size as well as the GULP size
+ */
+
+#define NUMBER_HGULPS (WINDOW_WIDTH/HGULP_SIZE)
+#define IMAGE_WIDTH   (HGULP_SIZE*NUMBER_HGULPS)
+#define IMAGE_LEFT    (((WINDOW_WIDTH-IMAGE_WIDTH) >> 1) + WINDOW_LEFT)
+#define IMAGE_HEIGHT  WINDOW_HEIGHT
+#define IMAGE_TOP     WINDOW_TOP
+
+/* This defines the number of pixels (in each direction) with will be
+ * processed on each pass through the innermost ray casting loop
+ */
+
+#define HGULP_SIZE  7
+#define VGULP_SIZE 16
+
+/* The following define the various meanings of hit.type */
+
+#define NO_HIT    0x00
+#define FRONT_HIT 0x00
+#define BACK_HIT  0x01
+#define FB_MASK   0x01
+#define X_HIT     0x00
+#define Y_HIT     0x02
+#define Z_HIT     0x04
+#define XYZ_MASK  0x06
+
+#define IS_FRONT_HIT(h) (((h)->type & FB_MASK) == FRONT_HIT)
+#define IS_BACK_HIT(h)  (((h)->type & FB_MASK) == BACK_HIT)
+#define IS_XRAY_HIT(h)  (((h)->type & XYZ_MASK) == X_HIT)
+#define IS_YRAY_HIT(h)  (((h)->type & XYZ_MASK) == Y_HIT)
+#define IS_ZRAY_HIT(h)  (((h)->type & XYZ_MASK) == Z_HIT)
+
+#define MK_HIT_TYPE(fb,xyz) ((fb)|(xyz))
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/* This structure provides the return values for each ray caster.  For
+ * performance reasons, the size of this structure should be an even
+ * power of two (makes index calculation faster).
+ */
+
+struct trv_rect_data_s;
+struct trv_raycast_s
+{
+  /* 'rect' points to the rectangle that was hit (if any) */
+
+  FAR struct trv_rect_data_s *rect;
+
+  uint8_t type;     /* Type of hit:  X/Y/Z cast, front/back */
+  uint8_t unused2;  /* Padding to force power of two size */
+  int16_t xpos;     /* Horizontal position on surface of the hit */
+  int16_t ypos;     /* Vertical position on surface of the hit */
+  int16_t xdist;    /* X distance to the hit */
+  int16_t ydist;    /* Y distance to the hit */
+  int16_t zdist;    /* Z distance to the hit (not used) */
+};
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/* This structure holds pre-calculated pitch data for all ray casts.  NOTE:
+ * would be a performance improvement if this structure is an even power of
+ *two in size (don't have to multiply to calculate indices)
+ */
+
+/* The following array describes the hits from X/Y/Z-ray casting for the
+ * current HGULP_SIZE x VGULP_SIZE cell
+ */
+
+extern struct trv_raycast_s g_ray_hit[VGULP_SIZE][HGULP_SIZE+1];
+
+/* This structure points to the double buffer row corresponding to the
+ * pitch angle
+ */
+
+extern uint8_t *g_buffer_row[VGULP_SIZE];
+
+/* The is the "column" offset in g_buffer_row for the current cell being
+ * operated on.  This value is updated in a loop by trv_raycaster.
+ */
+
+extern int16_t g_cell_column;
+
+/* This structure holds the parameters used in the current ray cast */
+
+extern struct trv_camera_s g_camera;
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#endif /* __APPS_GRAPHICS_TRAVELER_INCLUDE_TRV_RAYCAST_H */

graphics/traveler/include/trv_raycntl.h

@@ -64,5 +64,6 @@ struct trv_graphics_info_s;
 
 void trv_raycaster(FAR struct trv_camera_s *player,
                    FAR struct trv_graphics_info_s *ginfo);
+uint8_t trv_get_texture(uint8_t row, uint8_t col);
 
 #endif /* __APPS_GRAPHICS_TRAVELER_INCLUDE_TRV_RAYCNTL_H */

graphics/traveler/include/trv_rayrend.h

@@ -41,12 +41,37 @@
  ****************************************************************************/
 
 #include "trv_types.h"
-#include "trv_world.h"
 
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
 
+/* The following macro calculates the texture index for the given the
+ * horizontal position (h), the vertical position (v) and the log2 bitmap
+ * size (s).
+ */
+
+#define TMASK(s)       ((1 << (s)) - 1)
+#define TFIX(x,s)      ((x) << (s))
+#define TFRAC(x,m)     ((x) & (m))
+#define TNDX(h,v,s,m)  (TFIX( TFRAC( (~(v)), m ), s) + TFRAC( h, m ) )
+
+/* Here is a macro to extract one pixel from a WALL texture.  This is used
+ * by the raycasters to determine a hit in a transparent wall hit an
+ * opaque portion of the texture
+ */
+
+#define GET_FRONT_PIXEL(r,h,v) \
+   trv_get_rectpixel(h,v,g_even_bitmaps[ (r)->texture ], (r)->scale)
+#define GET_BACK_PIXEL(r,h,v) \
+   trv_get_rectpixel(h,v,g_odd_bitmaps[ (r)->texture ], (r)->scale)
+
+/* This is special value of a pixel in a "grandparent" rectangle which means
+ * that the pixel is transparent.
+ */
+
+#define INVISIBLE_PIXEL 0
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/
@@ -55,6 +80,17 @@
  * Public Function Prototypes
  ****************************************************************************/
 
-void trv_rend_backdrop (struct trv_camera_s *camera);
+struct trv_camera_s;
+struct trv_graphics_info_s;
+struct trv_bitmap_s;
+
+void trv_rend_backdrop(FAR struct trv_camera_s *camera,
+                       FAR struct trv_graphics_info_s *ginfo);
+void trv_rend_cell(uint8_t row, uint8_t col, uint8_t height, uint8_t width);
+void trv_rend_row(uint8_t row, uint8_t col, uint8_t width);
+void trv_rend_column(uint8_t row, uint8_t col, uint8_t height);
+void trv_rend_pixel(uint8_t row, uint8_t col);
+trv_pixel_t trv_get_rectpixel(int16_t hPos, int16_t vPos,
+                              FAR struct trv_bitmap_s *bmp, uint8_t scale);
 
 #endif /* __APPS_GRAPHICS_TRAVELER_INCLUDE_TRV_RAYEND_H */

graphics/traveler/include/trv_trigtbl.h

@@ -45,6 +45,7 @@
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
+/* Angles *******************************************************************/
 
 /* These are definitions of commonly used angles. */
 
@@ -69,6 +70,63 @@
 #define ANGLE_270   1440
 #define ANGLE_360   1920
 
+/* Fixed precision definitions **********************************************/
+
+/* SMALL precision (6 bits past binary point) */
+/* This occurs frequently because each CELL is 64x64 */
+
+#define sUNITY   64
+#define sHALF    32
+#define sQUARTER 16
+#define sSHIFT    6
+#define sMASK    63
+
+#define sTRUNC(a) ((a) >> sSHIFT)
+#define sROUND(a) (((a) + sHALF) >> sSHIFT)
+#define sFIX(a)   ((a) << sSHIFT)
+#define sSNAP(a)  ((a) & (~sMASK))
+#define sFRAC(a)  ((a) & sMASK)
+
+#define sMUL(a,b) (((int32_t)(a) * (int32_t)(b)) >> sSHIFT )
+#define sDIV(a,b) (((int32_t)(a) << sSHIFT) / (b))
+#define sFLOAT(a) ((float)(a) / (float)sUNITY)
+
+/* DOUBLE precision (12 bits past binary point) */
+/* This precision results when two SMALL precision numbers are multiplied */
+
+#define dUNITY 4096
+#define dHALF  2048
+#define dSHIFT   12
+#define dMASK  4095
+
+#define dTRUNC(a) ((a) >> dSHIFT)
+#define dROUND(a) (((a) + dHALF) >> dSHIFT)
+#define dFIX(a)   ((a) << dSHIFT)
+#define dSNAP(a)  ((a) & (~dMASK))
+#define dFRAC(a)  ((a) & dMASK)
+
+/* TRIPLE precision (18 bits past binary point) */
+/* This precision results when a SMALL and a DOUBLE precision number
+ * are multiplied
+ */
+
+#define tSHIFT     18
+
+/* QUAD precision (24 bits past binary point) */
+/* This precision results when two DOUBLE precision numbers are multiplied */
+
+#define qSHIFT     24
+
+/* BIG precision (16 bits past binary point) */
+/* This is convenient precision because it is easy to extract the integer
+ * portion without shifting or masking
+ */
+
+#define bUNITY 65536
+#define bHALF  32768
+#define bSHIFT    16
+#define bMASK  65535
+
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/

graphics/traveler/src/trv_main.c

@@ -257,7 +257,7 @@ int traveler_main(int argc, char *argv[])
 
       /* Paint the back drop */
 
-      trv_rend_backdrop(&g_trv_player);
+      trv_rend_backdrop(&g_trv_player, &g_trv_ginfo);
 
       /* Render the 3-D view */