Makefile

@@ -1,4 +1,4 @@
-CFLAGS = -ansi -pedantic -Wall -Wextra -O2 -Ofast -D_DEFAULT_SOURCE
+CFLAGS = -std=c11 -pedantic -Wall -Wextra -O2 -Ofast -D_DEFAULT_SOURCE
 LDFLAGS = -lX11 -lGL -lGLEW -lfftw3 -lm -lrt
 
 shadermeh: shadermeh.o window.o shader.o

shadermeh.c

@@ -21,47 +21,101 @@ static GLfloat vertex_buffer[] = {
 };
 
 static GLubyte audio_buffer[AUDIO_SAMPLES * AUDIO_CHANNELS];
-static float audio_sample_data[AUDIO_SAMPLES];
-static fftw_complex fftw_in[AUDIO_SAMPLES];
-static fftw_complex fftw_out[AUDIO_SAMPLES];
+size_t sample_pointer = 0;
+size_t sample_data_pointer = 0;
+size_t sample_rate = 0;
+static float *audio_sample_data;
+static float *audio_receive_data;
+static double *fftw_in;
+static fftw_complex *fftw_out;
 static fftw_plan plan;
 
-static int try_fetch_audio(void)
+static int try_fetch_audio(float iTimeDelta)
 {
-	size_t i, count = 0;
-	int ret;
+	/* To avoid generating stale images, we keep our own sample buffer,
+	 * which is then used to move a sliding window of data for the fft and
+	 * wave samples. We need to do this, as otherwise we would set an upper
+	 * limit of fps (20 at 4800kHz sample rate), which would not be good.
+	 * The size of the window is set in the header file. The with our
+	 * approach is that the buffer allows for drifting to occur within the
+	 * buffer limits. If you buffer is 3s long the delay can grow to 3s.
+	 * Choose your buffer size wisely for your application.
+	 */
+	size_t i;
+	ssize_t ret = 0;
+	memset(audio_receive_data, 0, AUDIO_BUFFER_SIZE * 
+		sizeof(*audio_receive_data));
+	sample_pointer += (sample_rate * iTimeDelta);
 
 	for (;;) {
-		ret = read(STDIN_FILENO,
-			   (char *)audio_sample_data + count,
-			   sizeof(audio_sample_data) - count);
+		ret = read(STDIN_FILENO, (char *)audio_receive_data,
+			sizeof(*audio_receive_data)*AUDIO_BUFFER_SIZE);
 
 		if (ret < 0) {
 			if (errno == EINTR)
 				continue;
-			if (errno == EAGAIN)
+			if (errno == EAGAIN || errno == EWOULDBLOCK)
 				break;
 			perror("stdin");
 			return -1;
 		}
 
-		if (ret == 0)
+		if (ret == 0 || ret % sizeof(float) != 0){
 			break;
+		}
 
-		count += ret;
+		ret /= 4;
+		if((ret + sample_pointer) > AUDIO_BUFFER_SIZE){
+			/* Not enough storage space to store all new audio data,
+			 * will override not output data with new one */
+			 memset(audio_sample_data, 0, 
+				AUDIO_BUFFER_SIZE * sizeof(*audio_sample_data));
+			 memcpy(audio_sample_data, audio_receive_data, 
+				ret * sizeof(*audio_sample_data));
+			 sample_pointer = 0;
+			 sample_data_pointer = ret;
+		}else{
+			memmove(audio_sample_data,
+				&audio_sample_data[sample_pointer], 
+				(AUDIO_BUFFER_SIZE - sample_pointer)*
+				sizeof(*audio_sample_data));
+			if(sample_data_pointer <= sample_pointer){
+				sample_data_pointer = 0;
+
+			}else{
+				sample_data_pointer -= sample_pointer;
+
+			}
+			sample_pointer = 0;
+			size_t len = ret;
+			if((ret + sample_data_pointer) >= AUDIO_BUFFER_SIZE){
+				len = AUDIO_BUFFER_SIZE - sample_data_pointer;
+			}
+			memcpy(&audio_sample_data[sample_data_pointer], 
+				audio_receive_data, len * sizeof(float));
+			sample_data_pointer += len;
+			break;
+		}
+
+	}
+	if((sample_pointer+AUDIO_FFT_SIZE) >= sample_data_pointer){
+		fprintf(stderr, "shadermeh input to slow %zu > %zu! wrapping around!\n", sample_pointer+AUDIO_FFT_SIZE, sample_data_pointer);
+		sample_pointer = 0;
 	}
 
-	for (i = 0; i < AUDIO_SAMPLES; ++i)
-		fftw_in[i][0] = audio_sample_data[i];
+	memset(fftw_in, 0, sizeof(*fftw_in) * AUDIO_BUFFER_SIZE);
+	memset(fftw_out, 0, sizeof(*fftw_out) * AUDIO_BUFFER_SIZE);
+
+	for (i = 0; i < AUDIO_FFT_SIZE; ++i)
+		fftw_in[i] = audio_sample_data[sample_pointer+i];
 
 	fftw_execute(plan);
 
 	for (i = 0; i < AUDIO_SAMPLES; ++i) {
-		float x = fftw_out[i][0], y = fftw_out[i][1];
-		float a = sqrt(x * x + y * y);
+		float a = cabs(fftw_out[i]);
 
-		audio_buffer[i + AUDIO_SAMPLES] = audio_sample_data[i] * 127.0f	+ 127.0f;
-		audio_buffer[i] = 127.0f + a * 127.0f;
+		audio_buffer[i + AUDIO_SAMPLES] = audio_sample_data[sample_pointer+i] * 127.0f	+ 127.0f;
+		audio_buffer[i] = log(fabsf(a)+1) * 50;
 	}
 
 	return 0;
@@ -159,11 +213,11 @@ static const struct option long_opts[] = {
  	{ "height", required_argument, NULL, 'h' },
 	{ "shader", required_argument, NULL, 's' },
 	{ "to-stdout", no_argument, NULL, 'S' },
-	{ "stdin-audio", no_argument, NULL, 'a' },
+	{ "stdin-audio", required_argument, NULL, 'a' },
 	{ NULL, 0, NULL, 0 },
 };
 
-static const char *short_opts = "w:h:s:Sa";
+static const char *short_opts = "w:a:h:s:S";
 
 static const char *usage_str =
 "shadermeh OPTIONS...\n"
@@ -174,7 +228,7 @@ static const char *usage_str =
 "  --height, -h <pixels>\n"
 "\n"
 "  --to-stdout, -S              Poop raw RGB24 frames to stdout (blocking)\n"
-"  --stdin-audio, -a            Read raw PCM audio from stdin (non-blocking)\n"
+"  --stdin-audio, -a <sample rate>     Read raw PCM audio from stdin (non-blocking)\n"
 "\n"
 "  --shader, -s <shader file>\n"
 "\n";
@@ -188,7 +242,7 @@ int main(int argc, char **argv)
 	void *fb32 = NULL, *fb24 = NULL;
 	const char *shader_file = NULL;
 	GLint major, minor, prog;
-	float iTime, iTimeDelta;
+	float iTime, iTimeDelta = 0;
 	bool have_audio = false;
 	bool to_stdout = false;
 	window *wnd;
@@ -218,6 +272,11 @@ int main(int argc, char **argv)
 			break;
 		case 'a':
 			have_audio = true;
+			sample_rate = strtol(optarg, NULL, 10);
+			audio_sample_data = malloc(AUDIO_BUFFER_SIZE * 
+				sizeof(float));
+			audio_receive_data = malloc(AUDIO_BUFFER_SIZE * 
+				sizeof(float));
 			break;
 		default:
 			fputs(usage_str, stderr);
@@ -341,8 +400,12 @@ int main(int argc, char **argv)
 	glBindSampler(0, sampler_sound);
 
 	if (have_audio) {
-		plan = fftw_plan_dft_1d(AUDIO_SAMPLES, fftw_in, fftw_out,
-					FFTW_FORWARD, FFTW_ESTIMATE);
+		fftw_in = fftw_alloc_real(AUDIO_BUFFER_SIZE);
+		fftw_out = fftw_alloc_complex(AUDIO_BUFFER_SIZE);
+		if(fftw_in == NULL || fftw_out == NULL)
+			goto fail_vao;
+		plan = fftw_plan_dft_r2c_1d(AUDIO_BUFFER_SIZE, fftw_in, fftw_out,
+			 FFTW_MEASURE);
 	}
 
 	/******************** framebuffer object ********************/
@@ -377,7 +440,7 @@ int main(int argc, char **argv)
 		glClear(GL_COLOR_BUFFER_BIT);
 
 		if (have_audio) {
-			if (try_fetch_audio())
+			if (try_fetch_audio(iTimeDelta))
 				break;
 
 			glBindTexture(GL_TEXTURE_2D, sound_tex);
@@ -451,6 +514,8 @@ fail_vao:
 	window_make_current(NULL);
 	free(fb32);
 	free(fb24);
+	fftw_free(fftw_in);
+	fftw_free(fftw_out);
 	window_destroy(wnd);
 	return EXIT_SUCCESS;
 }

shadermeh.h

@@ -27,10 +27,13 @@
 #include <poll.h>
 #include <time.h>
 
-#include <fftw3.h>
 #include <math.h>
+#include <complex.h>
+#include <fftw3.h>
 
-#define AUDIO_SAMPLES (512)
+#define AUDIO_SAMPLES (4096)
+#define AUDIO_BUFFER_SIZE (sample_rate * 3)
+#define AUDIO_FFT_SIZE (AUDIO_SAMPLES * 2)
 #define AUDIO_CHANNELS (2)
 
 typedef struct {

shaders/eclipse.frag

@@ -0,0 +1,84 @@
+// credit: https://www.shadertoy.com/view/4tGXzt
+
+#define BEATMOVE 1
+
+const float FREQ_RANGE = 64.0;
+const float PI = 3.1415;
+const float RADIUS = 0.6;
+const float BRIGHTNESS = 0.2;
+const float SPEED = 0.5;
+
+//convert HSV to RGB
+vec3 hsv2rgb(vec3 c){
+    vec4 K = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
+    vec3 p = abs(fract(c.xxx + K.xyz) * 6.0 - K.www);
+    return c.z * mix(K.xxx, clamp(p - K.xxx, 0.0, 1.0), c.y);
+}
+
+float luma(vec3 color) {
+  return dot(color, vec3(0.299, 0.587, 0.114));
+}
+
+float getfrequency(float x) {
+	return texture(iChannel0, vec2(floor(x * FREQ_RANGE + 1.0) / FREQ_RANGE, 0.25)).x + 0.06;
+}
+
+float getfrequency_smooth(float x) {
+	float index = floor(x * FREQ_RANGE) / FREQ_RANGE;
+    float next = floor(x * FREQ_RANGE + 1.0) / FREQ_RANGE;
+	return mix(getfrequency(index), getfrequency(next), smoothstep(0.0, 1.0, fract(x * FREQ_RANGE)));
+}
+
+float getfrequency_blend(float x) {
+    return mix(getfrequency(x), getfrequency_smooth(x), 0.5);
+}
+
+vec3 doHalo(vec2 fragment, float radius) {
+	float dist = length(fragment);
+	float ring = 1.0 / abs(dist - radius);
+	
+	float b = dist < radius ? BRIGHTNESS * 0.3 : BRIGHTNESS;
+	
+	vec3 col = vec3(0.0);
+	
+	float angle = atan(fragment.x, fragment.y);
+	col += hsv2rgb( vec3( ( angle + iTime * 0.25 ) / (PI * 2.0), 1.0, 1.0 ) ) * ring * b;
+	
+	float frequency = max(getfrequency_blend(abs(angle / PI)) - 0.02, 0.0);
+	col *= frequency;
+	
+	// Black halo
+	col *= smoothstep(radius * 0.5, radius, dist);
+	
+	return col;
+}
+
+vec3 doLine(vec2 fragment, float radius, float x) {
+	vec3 col = hsv2rgb(vec3(x * 0.23 + iTime * 0.12, 1.0, 1.0));
+	
+	float freq = abs(fragment.x * 0.5);
+	
+	col *= (1.0 / abs(fragment.y)) * BRIGHTNESS * getfrequency(freq);	
+	col = col * smoothstep(radius, radius * 1.8, abs(fragment.x));
+	
+	return col;
+}
+
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord ) {
+    vec2 fragPos = fragCoord / iResolution.xy;
+	fragPos = (fragPos - 0.5) * 2.0;
+    fragPos.x *= iResolution.x / iResolution.y;
+	
+	vec3 color = vec3(0.0134, 0.052, 0.1);
+	color += doHalo(fragPos, RADIUS);
+
+    float c = cos(iTime * SPEED);
+    float s = sin(iTime * SPEED);
+    vec2 rot = mat2(c,s,-s,c) * fragPos;
+	color += doLine(rot, RADIUS, rot.x);
+	
+	color += max(luma(color) - 1.0, 0.0);
+    
+	fragColor = vec4(color, 1.0);
+}

shaders/fft.frag

@@ -0,0 +1,65 @@
+/*
+
+	Linear vs Logarithmic FFT
+
+	some good test songs:
+
+	https://soundcloud.com/kraddy/winning
+	https://soundcloud.com/grey-houston/soothing-piano-melody
+	https://soundcloud.com/pointpoint/life-in-gr
+
+*/
+
+//from https://stackoverflow.com/questions/35799286
+float toLog(float value, float min, float max){
+	float exp = (value-min) / (max-min);
+	return min * pow(max/min, exp);
+}
+
+float getLevel(float samplePos){
+    // the sound texture is 512x2
+	int tx = int(samplePos*512.0);
+	// first row is frequency data (48Khz/4 in 512 texels, meaning 23 Hz per texel)
+	return texelFetch( iChannel0, ivec2(tx,0), 0 ).x; 
+}
+
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+	vec2 uv = fragCoord.xy / iResolution.xy;
+	
+    float xPos;
+    float fft;
+    
+    if (uv.y > 0.5){
+          
+        //linear sampling
+        xPos = uv.x;
+        fft = getLevel(xPos);
+        
+    }else{
+        
+        //crop bottom and top of range
+        uv.x = mix(0.3,0.7, uv.x);
+        
+        //logarithmic sampling
+        xPos = toLog(uv.x, 0.01, 1.0);
+
+        fft = getLevel(xPos);
+        
+        //boost contrast
+        fft = pow(fft,3.0);
+        
+        //boost gain
+        fft *= 1.5;
+        
+        //contrast / brightness
+        float contrast = 1.4;
+        float brightness = 0.;
+        fft = (fft - 0.5) * contrast + 0.5 + brightness;
+        
+    }
+    
+    fragColor = vec4(vec3(fft),1.0);
+       
+}

shaders/grid.frag

@@ -0,0 +1,158 @@
+//https://www.shadertoy.com/view/XlBXRh with mic not soundcloud
+#define preset4
+
+#ifdef preset1
+	#define cells vec2(14.,14.)
+	#define persp 1.5
+	#define height 1.
+	#define linewidth .5
+	#define lineexp 4.
+	#define brightness .7
+#endif
+
+
+#ifdef preset2
+	#define cells vec2(10.,5.)
+	#define persp 2.5
+	#define height 1.
+	#define linewidth 3.
+	#define lineexp 6.
+	#define brightness .4
+#endif
+
+
+#ifdef preset3
+	#define OPAQUE_MODE
+	#define INVERSE
+	#define cells vec2(16.,16.)
+	#define persp 1.
+	#define height 1.5
+	#define linewidth .1
+	#define lineexp .5
+	#define brightness .8
+#endif
+
+#ifdef preset4
+	#define OPAQUE_MODE
+	#define cells vec2(10.,10.)
+	#define persp 2.
+	#define height .75
+	#define linewidth .2
+	#define lineexp 1.
+	#define brightness 1.5
+#endif
+
+#ifdef preset5
+	#define INVERSE
+	#define cells vec2(6.,25.)
+	#define persp 1.
+	#define height 2.
+	#define linewidth .07
+	#define lineexp .3
+	#define brightness .35
+#endif
+
+
+#ifdef preset6
+	#define INVERSE
+	#define OPAQUE_MODE
+	#define cells vec2(15.,15.)
+	#define persp 2.5
+	#define height 1.
+	#define linewidth .05
+	#define lineexp .5
+	#define brightness 1.
+#endif
+
+
+
+
+#define hcells (cells*.5)
+
+
+vec3 segment(vec2 p, vec3 from, vec3 to, float width, float dist) {
+width=1./width;
+vec2 seg=from.xy-to.xy;
+float halfdist=distance(from.xy,to.xy)*.5;
+float ang=atan(seg.y,seg.x);
+float sine=sin(ang);
+float cose=cos(ang);
+p-=from.xy; 
+p*=mat2(cose,sine,-sine,cose);
+float dx=abs(p.x+halfdist)-halfdist;
+float dy=abs(p.y);
+float h=1.-abs(p.x+halfdist*2.)/halfdist/2.;
+float pz=-from.z-(to.z-from.z)*h;
+float l=1.-clamp(max(dx,dy)*width/(pz+dist)*dist*dist,0.,.1)/.1;
+l=pow(abs(l),lineexp)*(1.-pow(clamp(abs(dist-pz)*.45,0.,1.),.5))*4.;
+return normalize(.25+abs(mix(from,to,h)))*l;
+}
+
+mat3 rotmat(vec3 v, float angle)
+{
+	angle=radians(angle);
+	float c = cos(angle);
+	float s = sin(angle);
+	
+	return mat3(c + (1.0 - c) * v.x * v.x, (1.0 - c) * v.x * v.y - s * v.z, (1.0 - c) * v.x * v.z + s * v.y,
+		(1.0 - c) * v.x * v.y + s * v.z, c + (1.0 - c) * v.y * v.y, (1.0 - c) * v.y * v.z - s * v.x,
+		(1.0 - c) * v.x * v.z - s * v.y, (1.0 - c) * v.y * v.z + s * v.x, c + (1.0 - c) * v.z * v.z
+		);
+}
+
+float getz(vec2 xy) {
+xy=xy*10.+hcells;
+//float pos=length(pow(abs(xy/cells),vec2(3.)))*8.;
+float pos=(xy.y*cells.x+xy.x)/(cells.x*cells.y);
+float s=texture(iChannel0,vec2(.5+pos*.5,.1)).x;
+return .25-pow(s,1.5)*height;
+}
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+	vec2 uv = (gl_FragCoord.xy / iResolution.xy-.5)*2.;
+	uv.y*=iResolution.y/iResolution.x;
+	mat3 camrot=rotmat(normalize(vec3(0.,0.,1.)),iTime*25.)*rotmat(normalize(vec3(1.,0.*sin(iTime*.5),0.)),60.+30.*sin(iTime*.5));
+	float s=.1,maxc=0.;
+	vec3 p1,p2,p3;
+	vec3 rotv=vec3(0.,0.,1.);
+	float h;
+	vec3 col=vec3(0.);
+	float dist=1.2+pow(abs(sin(iTime*.3)),5.)*.5;
+	vec3 c=vec3(0.);
+	for (float y=0.; y<cells.y; y++) {
+		for (float x=0.; x<cells.x; x++) {
+			p1=vec3(x-hcells.x,y-hcells.y,0.)*.1; p1.z=getz(p1.xy);
+			p2=vec3(p1.x+.1,p1.y   ,0.); p2.z=getz(p2.xy);
+			p3=vec3(p1.x   ,p1.y+.1,0.); p3.z=getz(p3.xy);
+			p1*=camrot; p2*=camrot; p3*=camrot;
+			p1.xy*=persp/max(0.1,p1.z+dist);
+			p2.xy*=persp/max(0.1,p2.z+dist);
+			p3.xy*=persp/max(0.1,p3.z+dist);
+			if (max(p1.x,p2.x)>uv.x-linewidth/4. && min(p1.x,p2.x)<uv.x+linewidth/4. && x<cells.x-1.) {
+				if (max(p1.y,p2.y)>uv.y-linewidth/4. && min(p1.y,p2.y)<uv.y+linewidth/4.) {
+					#ifdef OPAQUE_MODE
+						c=max(c,segment(uv,p1,p2,linewidth,dist)*1.5);
+					#else
+						c+=segment(uv,p1,p2,linewidth,dist);
+					#endif
+				}
+			}
+			if (max(p1.x,p3.x)>uv.x-linewidth/4. && min(p1.x,p3.x)<uv.x+linewidth/4. && y<cells.y-1.) {
+				if (max(p1.y,p3.y)>uv.y-linewidth/4. && min(p1.y,p3.y)<uv.y+linewidth/4.) {
+					#ifdef OPAQUE_MODE
+						c=max(c,segment(uv,p1,p3,linewidth,dist)*1.5);
+					#else
+						c+=segment(uv,p1,p3,linewidth,dist);
+					#endif
+				}
+			}
+		}
+	}
+	c*=brightness;
+#ifdef INVERSE
+	fragColor = vec4(1.-c,1.);
+#else
+	fragColor = vec4(c,1.);
+#endif
+}

shaders/spectrum.frag

@@ -0,0 +1,38 @@
+/*
+2D LED Spectrum - Visualiser
+Based on Led Spectrum Analyser by: simesgreen - 27th February, 2013 https://www.shadertoy.com/view/Msl3zr
+2D LED Spectrum by: uNiversal - 27th May, 2015
+Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
+*/
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+    // create pixel coordinates
+    vec2 uv = fragCoord.xy / iResolution.xy;
+
+    // quantize coordinates
+    const float bands = 30.0;
+    const float segs = 40.0;
+    vec2 p;
+    p.x = floor(uv.x*bands)/bands;
+    p.y = floor(uv.y*segs)/segs;
+
+    // read frequency data from first row of texture
+    float fft  = texture( iChannel0, vec2(p.x,0.0) ).x;
+
+    // led color
+    vec3 color = mix(vec3(0.0, 2.0, 0.0), vec3(2.0, 0.0, 0.0), sqrt(uv.y));
+
+    // mask for bar graph
+    float mask = (p.y < fft) ? 1.0 : 0.1;
+
+    // led shape
+    vec2 d = fract((uv - p) *vec2(bands, segs)) - 0.5;
+    float led = smoothstep(0.5, 0.35, abs(d.x)) *
+                smoothstep(0.5, 0.35, abs(d.y));
+    vec3 ledColor = led*color*mask;
+
+    // output final color
+    fragColor = vec4(ledColor, 1.0);
+}
+