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-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
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index 0000000000..a2f58cd8a6
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+++ 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