I guess I can just put this up. Most of these have been sitting here forever.

fuzz.c

@@ -0,0 +1,200 @@
+/*
+	fuzz.c : Fancy software filter.
+	I was bored.
+	(C)2016 Marisa Kirisame, UnSX Team.
+	Released under the GNU GPLv3 (or later).
+*/
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_ttf.h>
+#include <time.h>
+
+typedef struct
+{
+	float r,g,b,a;
+} rgbfpx_t;
+
+typedef struct
+{
+	Uint8 r,g,b,a;
+} __attribute__((packed)) rgb8px_t;
+
+float t = 0.f;
+const int fw = 640, fh = 480;
+
+float rn( float sdx, float sdy )
+{
+	return cosf(sdy*3874.8674f+sdx*6783.5325f)*2737.8474f;
+}
+
+float fract( float x )
+{
+	return x-floorf(x);
+}
+
+SDL_Window *w;
+SDL_Surface *ws, *fz;
+
+rgbfpx_t *fl1, *fl2, *fl3;
+const int fw1 = 320, fw2 = 160, fw3 = 80, fh1 = 240, fh2 = 120, fh3 = 60;
+
+void mklayer1( void )
+{
+	for ( int y=0; y<fh1; y++ )
+	{
+		float rg;
+		for ( int x=0; x<fw1; x++ )
+		{
+			rg = 2.f*fabsf(fract(rn(x,y)+t*1.3526f)-0.5f);
+			fl1[x+y*fw1].r = 0.71f*rg;
+			fl1[x+y*fw1].g = 0.67f*rg;
+			fl1[x+y*fw1].b = 0.95f*rg;
+			fl1[x+y*fw1].a = 1.f*rg;
+		}
+	}
+}
+
+void mklayer2( void )
+{
+	for ( int y=0; y<fh2; y++ )
+	{
+		float rg;
+		for ( int x=0; x<fw2; x++ )
+		{
+			rg = 2.f*fabsf(fract(rn(x,y)+t*0.7843f)-0.5f);
+			fl2[x+y*fw2].r = 0.66f*rg;
+			fl2[x+y*fw2].g = 0.84f*rg;
+			fl2[x+y*fw2].b = 0.73f*rg;
+			fl2[x+y*fw2].a = 1.f*rg;
+		}
+	}
+}
+
+void mklayer3( void )
+{
+	for ( int y=0; y<fh3; y++ )
+	{
+		float rg;
+		for ( int x=0; x<fw3; x++ )
+		{
+			rg = 2.f*fabsf(fract(rn(x,y)+t*0.3725f)-0.5f);
+			fl3[x+y*fw3].r = 0.95f*rg;
+			fl3[x+y*fw3].g = 0.73f*rg;
+			fl3[x+y*fw3].b = 0.81f*rg;
+			fl3[x+y*fw3].a = 1.f*rg;
+		}
+	}
+}
+
+void mergedown( void )
+{
+	rgbfpx_t twofivefive = {255.f,255.f,255.f,255.f};
+	#pragma omp parallel for
+	for ( int y=0; y<fh; y++ )
+	{
+		int y1, y2, y3;
+		rgb8px_t *stripe;
+		rgbfpx_t merged;
+		y1 = y>>1;
+		y2 = y>>2;
+		y3 = y>>3;
+		stripe = (rgb8px_t*)((Uint8*)fz->pixels+y*fz->pitch);
+		for ( int x=0; x<fw; x++ )
+		{
+			int x1, x2, x3;
+			x1 = x>>1;
+			x2 = x>>2;
+			x3 = x>>3;
+			// gcc is stupid
+			asm(	"movaps %1,%%xmm0\n"
+				"mulps %2,%%xmm0\n"
+				"mulps %3,%%xmm0\n"
+				"mulps %4,%%xmm0\n"
+				"movaps %%xmm0,%0\n"
+				:"=m"(merged)
+				:"m"(fl1[x1+y1*fw1]),"m"(fl2[x2+y2*fw2]),
+				"m"(fl3[x3+y3*fw3]),"m"(twofivefive));
+			stripe[x].r = merged.r;
+			stripe[x].g = merged.g;
+			stripe[x].b = merged.b;
+			stripe[x].a = merged.a;
+		}
+	}
+}
+
+#define TMAX 64
+int ti = 0;
+float ts = 0.f, tl[TMAX] = {0.f};
+
+float avg_fps( float nt )
+{
+	ts = ts-tl[ti]+nt;
+	tl[ti] = nt;
+	if ( ++ti == TMAX ) ti = 0;
+	return ts/TMAX;
+}
+
+#define NANOS_SEC 1000000000L
+
+long ticker( void )
+{
+	struct timespec ts;
+	clock_gettime(CLOCK_MONOTONIC_RAW,&ts);
+	return ts.tv_nsec+ts.tv_sec*NANOS_SEC;
+}
+
+int main( void )
+{
+	SDL_Init(SDL_INIT_VIDEO|SDL_INIT_TIMER|SDL_INIT_EVENTS);
+	w = SDL_CreateWindow("Fuzz",SDL_WINDOWPOS_UNDEFINED,
+		SDL_WINDOWPOS_UNDEFINED,fw,fh,SDL_WINDOW_SHOWN);
+	ws = SDL_GetWindowSurface(w);
+	fz = SDL_CreateRGBSurface(0,fw,fh,32,0xFF,0xFF00,0xFF0000,0xFF000000);
+	SDL_SetSurfaceBlendMode(fz,SDL_BLENDMODE_NONE);
+	fl1 = malloc(sizeof(rgbfpx_t)*fw1*fh1);
+	fl2 = malloc(sizeof(rgbfpx_t)*fw2*fh2);
+	fl3 = malloc(sizeof(rgbfpx_t)*fw3*fh3);
+	TTF_Init();
+	TTF_Font *fon = TTF_OpenFont("/usr/share/fonts/misc/unifont.bdf",16);
+	SDL_Event e;
+	SDL_Color fpscol = {160,0,0,255};
+	int active = 1;
+	long tick, tock;
+	float frame = 0.f, fps = NAN, fpsmin = INFINITY, fpsmax = -INFINITY,
+		fpsavg = 0.f;
+	char fpst[16];
+	while ( active )
+	{
+		tick = ticker();
+		while ( SDL_PollEvent(&e) ) if ( (e.type == SDL_QUIT)
+			|| ((e.type == SDL_KEYDOWN)
+			&& (e.key.keysym.sym == SDLK_ESCAPE)) ) active = 0;
+		mklayer1();
+		mklayer2();
+		mklayer3();
+		mergedown();
+		SDL_BlitSurface(fz,0,ws,0);
+		snprintf(fpst,15,"%.2f FPS",fps);
+		SDL_Surface *txt = TTF_RenderText_Blended(fon,fpst,fpscol);
+		SDL_BlitSurface(txt,0,ws,0);
+		SDL_FreeSurface(txt);
+		SDL_UpdateWindowSurface(w);
+		tock = ticker();
+		frame = (float)(tock-tick)/NANOS_SEC;
+		fps = 1.f/frame;
+		fpsavg = avg_fps(fps);
+		if ( fps > fpsmax ) fpsmax = fps;
+		if ( fps < fpsmin ) fpsmin = fps;
+		printf("FPS: %.2f (%.2f min, %.2f max, %.2f avg)\n",fps,
+			fpsmin,fpsmax,fpsavg);
+		t += frame;
+	}
+	TTF_CloseFont(fon);
+	TTF_Quit();
+	free(fl3);
+	free(fl2);
+	free(fl1);
+	SDL_FreeSurface(fz);
+	SDL_DestroyWindow(w);
+	SDL_Quit();
+	return 0;
+}