summaryrefslogtreecommitdiffstats
path: root/apps/plugins/sdl/progs/wolf3d/wl_cloudsky.c
diff options
context:
space:
mode:
authorFranklin Wei <git@fwei.tk>2019-07-07 22:00:20 -0400
committerFranklin Wei <git@fwei.tk>2019-07-09 11:20:55 -0400
commit3f59fc8b771625aca9c3aefe03cf1038d8461963 (patch)
treee0623a323613baa0b0993411b38bcaed144b27ed /apps/plugins/sdl/progs/wolf3d/wl_cloudsky.c
parent439a0d1d91fa040d261fc39b87278bc9f5391dcc (diff)
downloadrockbox-3f59fc8b771625aca9c3aefe03cf1038d8461963.tar.gz
rockbox-3f59fc8b771625aca9c3aefe03cf1038d8461963.tar.bz2
rockbox-3f59fc8b771625aca9c3aefe03cf1038d8461963.zip
Wolfenstein 3-D!
This is a port of Wolf4SDL, which is derived from the original id software source release. The port runs on top of the SDL plugin runtime and is loaded as an overlay. Licensing of the game code is not an issue, as discussed below (essentially, the Debian project treats Wolf4SDL as GPLv2, with an email from John Carmack backing it up): http://forums.rockbox.org/index.php?topic=52872 Included is a copy of MAME's Yamaha OPL sound chip emulator (fmopl_gpl.c). This file was not part of the original Wolf4SDL source (which includes a non-GPL'd version), but was rather rebased from from a later MAME source which had been relicensed to GPLv2. Change-Id: I64c2ba035e0be7e2f49252f40640641416613439
Diffstat (limited to 'apps/plugins/sdl/progs/wolf3d/wl_cloudsky.c')
-rw-r--r--apps/plugins/sdl/progs/wolf3d/wl_cloudsky.c259
1 files changed, 259 insertions, 0 deletions
diff --git a/apps/plugins/sdl/progs/wolf3d/wl_cloudsky.c b/apps/plugins/sdl/progs/wolf3d/wl_cloudsky.c
new file mode 100644
index 0000000000..a2f58cd8a6
--- /dev/null
+++ b/apps/plugins/sdl/progs/wolf3d/wl_cloudsky.c
@@ -0,0 +1,259 @@
+#include "version.h"
+
+#ifdef USE_CLOUDSKY
+
+#include "wl_def.h"
+#include "wl_cloudsky.h"
+
+// Each colormap defines a number of colors which should be mapped from
+// the skytable. The according colormapentry_t array defines how these colors should
+// be mapped to the wolfenstein palette. The first int of each entry defines
+// how many colors are grouped to this entry and the absolute value of the
+// second int sets the starting palette index for this pair. If this value is
+// negative the index will be decremented for every color, if it's positive
+// it will be incremented.
+//
+// Example colormap:
+// colormapentry_t colmapents_1[] = { { 6, -10 }, { 2, 40 } };
+// colormap_t colorMaps[] = {
+// { 8, colmapents_1 }
+// };
+//
+// The colormap 0 consists of 8 colors. The first color group consists of 6
+// colors and starts descending at palette index 10: 10, 9, 8, 7, 6, 5
+// The second color group consists of 2 colors and starts ascending at
+// index 40: 40, 41
+// There's no other color group because all colors of this colormap are
+// already used (6+2=8)
+//
+// Warning: Always make sure that the sum of the amount of the colors in all
+// color groups is the number of colors used for your colormap!
+
+colormapentry_t colmapents_1[] = { { 16, -31 }, { 16, 136 } };
+colormapentry_t colmapents_2[] = { { 16, -31 } };
+
+colormap_t colorMaps[] = {
+ { 32, colmapents_1 },
+ { 16, colmapents_2 }
+};
+
+const int numColorMaps = lengthof(colorMaps);
+
+// The sky definitions which can be selected as defined by GetCloudSkyDefID() in wl_def.h
+// You can use <TAB>+Z in debug mode to find out suitable values for seed and colorMapIndex
+// Each entry consists of seed, speed, angle and colorMapIndex
+cloudsky_t cloudSkys[] = {
+ { 626, 800, 20, 0 },
+ { 1234, 650, 60, 1 },
+ { 0, 700, 120, 0 },
+ { 0, 0, 0, 0 },
+ { 11243, 750, 310, 0 },
+ { 32141, 750, 87, 0 },
+ { 12124, 750, 64, 0 },
+ { 55543, 500, 240, 0 },
+ { 65535, 200, 54, 1 },
+ { 4, 1200, 290, 0 },
+};
+
+byte skyc[65536L];
+
+long cloudx = 0, cloudy = 0;
+cloudsky_t *curSky = NULL;
+
+#ifdef USE_FEATUREFLAGS
+
+// The lower left tile of every map determines the used cloud sky definition from cloudSkys.
+static int GetCloudSkyDefID()
+{
+ int skyID = ffDataBottomLeft;
+ assert(skyID >= 0 && skyID < lengthof(cloudSkys));
+ return skyID;
+}
+
+#else
+
+static int GetCloudSkyDefID()
+{
+ int skyID;
+ switch(gamestate.episode * 10 + mapon)
+ {
+ case 0: skyID = 0; break;
+ case 1: skyID = 1; break;
+ case 2: skyID = 2; break;
+ case 3: skyID = 3; break;
+ case 4: skyID = 4; break;
+ case 5: skyID = 5; break;
+ case 6: skyID = 6; break;
+ case 7: skyID = 7; break;
+ case 8: skyID = 8; break;
+ case 9: skyID = 9; break;
+ default: skyID = 9; break;
+ }
+ assert(skyID >= 0 && skyID < lengthof(cloudSkys));
+ return skyID;
+}
+
+#endif
+
+void SplitS(unsigned size,unsigned x1,unsigned y1,unsigned x2,unsigned y2)
+{
+ if(size==1) return;
+ if(!skyc[((x1+size/2)*256+y1)])
+ {
+ skyc[((x1+size/2)*256+y1)]=(byte)(((int)skyc[(x1*256+y1)]
+ +(int)skyc[((x2&0xff)*256+y1)])/2)+rand()%(size*2)-size;
+ if(!skyc[((x1+size/2)*256+y1)]) skyc[((x1+size/2)*256+y1)]=1;
+ }
+ if(!skyc[((x1+size/2)*256+(y2&0xff))])
+ {
+ skyc[((x1+size/2)*256+(y2&0xff))]=(byte)(((int)skyc[(x1*256+(y2&0xff))]
+ +(int)skyc[((x2&0xff)*256+(y2&0xff))])/2)+rand()%(size*2)-size;
+ if(!skyc[((x1+size/2)*256+(y2&0xff))])
+ skyc[((x1+size/2)*256+(y2&0xff))]=1;
+ }
+ if(!skyc[(x1*256+y1+size/2)])
+ {
+ skyc[(x1*256+y1+size/2)]=(byte)(((int)skyc[(x1*256+y1)]
+ +(int)skyc[(x1*256+(y2&0xff))])/2)+rand()%(size*2)-size;
+ if(!skyc[(x1*256+y1+size/2)]) skyc[(x1*256+y1+size/2)]=1;
+ }
+ if(!skyc[((x2&0xff)*256+y1+size/2)])
+ {
+ skyc[((x2&0xff)*256+y1+size/2)]=(byte)(((int)skyc[((x2&0xff)*256+y1)]
+ +(int)skyc[((x2&0xff)*256+(y2&0xff))])/2)+rand()%(size*2)-size;
+ if(!skyc[((x2&0xff)*256+y1+size/2)]) skyc[((x2&0xff)*256+y1+size/2)]=1;
+ }
+
+ skyc[((x1+size/2)*256+y1+size/2)]=(byte)(((int)skyc[(x1*256+y1)]
+ +(int)skyc[((x2&0xff)*256+y1)]+(int)skyc[(x1*256+(y2&0xff))]
+ +(int)skyc[((x2&0xff)*256+(y2&0xff))])/4)+rand()%(size*2)-size;
+
+ SplitS(size/2,x1,y1+size/2,x1+size/2,y2);
+ SplitS(size/2,x1+size/2,y1,x2,y1+size/2);
+ SplitS(size/2,x1+size/2,y1+size/2,x2,y2);
+ SplitS(size/2,x1,y1,x1+size/2,y1+size/2);
+}
+
+void InitSky()
+{
+ unsigned cloudskyid = GetCloudSkyDefID();
+ if(cloudskyid >= lengthof(cloudSkys))
+ Quit("Illegal cloud sky id: %u", cloudskyid);
+ curSky = &cloudSkys[cloudskyid];
+
+ memset(skyc, 0, sizeof(skyc));
+ // funny water texture if used instead of memset ;D
+ // for(int i = 0; i < 65536; i++)
+ // skyc[i] = rand() % 32 * 8;
+
+ srand(curSky->seed);
+ skyc[0] = rand() % 256;
+ SplitS(256, 0, 0, 256, 256);
+
+ // Smooth the clouds a bit
+ for(int k = 0; k < 2; k++)
+ {
+ for(int i = 0; i < 256; i++)
+ {
+ for(int j = 0; j < 256; j++)
+ {
+ int32_t val = -skyc[j * 256 + i];
+ for(int m = 0; m < 3; m++)
+ {
+ for(int n = 0; n < 3; n++)
+ {
+ val += skyc[((j + n - 1) & 0xff) * 256 + ((i + m - 1) & 0xff)];
+ }
+ }
+ skyc[j * 256 + i] = (byte)(val >> 3);
+ }
+ }
+ }
+
+ // the following commented line could be useful, if you're trying to
+ // create a new color map. This will display your current color map
+ // in one (of course repeating) stripe of the sky
+
+ // for(int i = 0; i < 256; i++)
+ // skyc[i] = skyc[i + 256] = skyc[i + 512] = i;
+
+ if(curSky->colorMapIndex >= lengthof(colorMaps))
+ Quit("Illegal colorMapIndex for cloud sky def %u: %u", cloudskyid, curSky->colorMapIndex);
+
+ colormap_t *curMap = &colorMaps[curSky->colorMapIndex];
+ int numColors = curMap->numColors;
+ byte colormap[256];
+ colormapentry_t *curEntry = curMap->entries;
+ for(int calcedCols = 0; calcedCols < numColors; curEntry++)
+ {
+ if(curEntry->startAndDir < 0)
+ {
+ for(int i = 0, ind = -curEntry->startAndDir; i < curEntry->length; i++, ind--)
+ colormap[calcedCols++] = ind;
+ }
+ else
+ {
+ for(int i = 0, ind = curEntry->startAndDir; i < curEntry->length; i++, ind++)
+ colormap[calcedCols++] = ind;
+ }
+ }
+
+ for(int i = 0; i < 256; i++)
+ {
+ for(int j = 0; j < 256; j++)
+ {
+ skyc[i * 256 + j] = colormap[skyc[i * 256 + j] * numColors / 256];
+ }
+ }
+}
+
+// Based on Textured Floor and Ceiling by DarkOne
+void DrawClouds(byte *vbuf, unsigned vbufPitch, int min_wallheight)
+{
+ // Move clouds
+ fixed moveDist = tics * curSky->speed;
+ cloudx += FixedMul(moveDist,sintable[curSky->angle]);
+ cloudy -= FixedMul(moveDist,costable[curSky->angle]);
+
+ // Draw them
+ int y0, halfheight;
+ unsigned top_offset0;
+ fixed dist; // distance to row projection
+ fixed tex_step; // global step per one screen pixel
+ fixed gu, gv, du, dv; // global texture coordinates
+ int u, v; // local texture coordinates
+
+ // ------ * prepare * --------
+ halfheight = viewheight >> 1;
+ y0 = min_wallheight >> 3; // starting y value
+ if(y0 > halfheight)
+ return; // view obscured by walls
+ if(!y0) y0 = 1; // don't let division by zero
+ top_offset0 = vbufPitch * (halfheight - y0 - 1);
+
+ // draw horizontal lines
+ for(int y = y0, top_offset = top_offset0; y < halfheight; y++, top_offset -= vbufPitch)
+ {
+ dist = (heightnumerator / y) << 8;
+ gu = viewx + FixedMul(dist, viewcos) + cloudx;
+ gv = -viewy + FixedMul(dist, viewsin) + cloudy;
+ tex_step = (dist << 8) / viewwidth / 175;
+ du = FixedMul(tex_step, viewsin);
+ dv = -FixedMul(tex_step, viewcos);
+ gu -= (viewwidth >> 1)*du;
+ gv -= (viewwidth >> 1)*dv; // starting point (leftmost)
+ for(int x = 0, top_add = top_offset; x < viewwidth; x++, top_add++)
+ {
+ if(wallheight[x] >> 3 <= y)
+ {
+ u = (gu >> 13) & 255;
+ v = (gv >> 13) & 255;
+ vbuf[top_add] = skyc[((255 - u) << 8) + 255 - v];
+ }
+ gu += du;
+ gv += dv;
+ }
+ }
+}
+
+#endif