removed aliasing in rect and saw oscilators

examples/curlywas/tim_ges.cwa

@@ -1,3 +1,5 @@
+import "env.memory" memory(4);
+
 fn melody(ch: i32, t: i32, T: i32) {
     let lazy riff_pos = abs(((T&31) - 16) as f32) as i32;
     let lazy shift = ((1-((T>>5)&3))%2-1) * 2;
@@ -7,7 +9,7 @@ fn melody(ch: i32, t: i32, T: i32) {
     let inline riff_note = 5514 >> (riff_pos % note_count * 4) & 15;
     let inline melody_note = shift + octave - riff_note;
 
-    ch?1 = riff_pos * 10 + 4;
+    ch?1 = riff_pos * 10 + 63;
     ch?3 = melody_note + 64;
 
     let inline arp_note = shift + ((0x85>>((t/2)%3*4)) & 15) - 1;
@@ -36,12 +38,12 @@ export fn upd() {
 
 data 80 {
     i8(
-        0, 64, 0, 128, 0, 0x90,
-        0, 128, 0, 128, 0, 0x4c,
+        0, 80, 0, 128, 0, 0x90,
+        0, 80, 0, 128, 0, 0x4c,
         5, 128, 0, 128, 0, 0x4c,
         5, 128, 0, 128, 0, 0x4c,
         0xf8, 0x85,
-        0x81, 0x81, 0, 105, 0, 80
+        0x81, 0x81, 0, 110, 0, 80
     )
 }
 

platform/src/ges.cwa

@@ -34,8 +34,9 @@ export fn gesSnd(t: i32) -> f32 {
             channelState?GesChannelState.Trigger = ctrl;
 
             if envState {
-                envVol = envVol + 8 * pow(1.5625, (15 - channelReg?4 & 15) as f32) as i32;
-                if envVol >= 65535 {
+                let lazy attack = channelReg?4 & 15;
+                envVol = envVol + 12 * pow(1.5625, (15 - attack) as f32) as i32;
+                if envVol >= 65535 | !attack {
                     envVol = 65535;
                     envState = 0;
                 }
@@ -61,31 +62,45 @@ export fn gesSnd(t: i32) -> f32 {
 
             let inline pulseWidth = channelReg?1;
             let phaseShift = (pulseWidth - 128) * 255;
+            let invPhaseInc = 1 as f32 / phaseInc as f32;
 
             i = 0;
             let wave = ctrl >> 6;
             if wave < 2 {
                 if wave {
+                    let pulsePhase1 = pulseWidth << 23;
+                    let pulsePhase2 = (511 - pulseWidth) << 23;
                     loop sawLoop {
-                        i!(GesBufferOffset + 128*4) = (phase & 65535) - 32768;
+                        let p = (phase ^ 32768) << 16;
+                        let saw = (p >> 16) - polyBlep(phase, invPhaseInc, -32767);
+                        let saw2 = select(p #>= pulsePhase1 & p #< pulsePhase2, -saw, saw);
+                        let saw2 = saw2 -
+                            polyBlep((p - pulsePhase1) >> 16, invPhaseInc, -saw) -
+                            polyBlep((p - pulsePhase2) >> 16, invPhaseInc, saw);
+                        i!(GesBufferOffset + 128*4) = saw2;
                         phase = phase + phaseInc;
                         branch_if (i := i + 4) < 64*4: sawLoop;
                     }
                 }
                 else
                 {
+                    let pulsePhase = 32768 + pulseWidth * 128;
                     loop rectLoop {
-                        let p = (phase & 65535) + phaseShift;
-                        i!(GesBufferOffset + 128*4) = select(p >= 32768, -32768, 32767);
+                        i!(GesBufferOffset + 128*4) = select((phase & 65535) < pulsePhase, -32768, 32767) -
+                            polyBlep(phase, invPhaseInc, -32767) -
+                            polyBlep(phase - pulsePhase, invPhaseInc, 32767);
                         phase = phase + phaseInc;
                         branch_if (i := i + 4) < 64*4: rectLoop;
                     }
                 }
             } else {
                 if wave == 2 {
+                    let scale = pulseWidth + 256;
                     loop triLoop {
                         let s = phase << 16;
-                        s = s ^ (s >> 31);
+                        s = (s ^ (s >> 31));
+                        s = (s >> 8) * scale;
+                        s = (s ^ (s >> 31));
                         i!(GesBufferOffset + 128*4) = (s >> 15) - 32768;
                         phase = phase + phaseInc;
                         branch_if (i := i + 4) < 64*4: triLoop;
@@ -93,9 +108,10 @@ export fn gesSnd(t: i32) -> f32 {
                 } else {
                     loop noiseLoop {
                         let s = (phase >> 12) & 4095;
+                        let pulse = ((phase >> 8) & 255) >= pulseWidth;
                         s = s * 0x6746ba73;
-                        s = s ^ (s >> 15);
-                        i!(GesBufferOffset + 128*4) = (s * 0x83567a92) >> 16;
+                        s = s ^ (s >> 15) * pulse;
+                        i!(GesBufferOffset + 128*4) = (s * 0x83567a92 + (phase << 16)) >> 16;
                         phase = phase + phaseInc;
                         branch_if (i := i + 4) < 64*4: noiseLoop;
                     }
@@ -124,8 +140,12 @@ export fn gesSnd(t: i32) -> f32 {
                 let ctrl = filter?0x6a;
                 let note = i32.load16_u(filter * 2, 0x6c);
                 let inline freq = 440 as f32 * pow(2.0, (note - 69*256) as f32 / (12*256) as f32);
-                let F = min(4096 as f32, 8192 as f32 * sin(freq * (3.1415 / 44100.0))) as i32;
-                let Q = 7350 - ctrl * (6530/255);
+                let F = (8192 as f32 * sin(min(0.25, freq / 44100 as f32) * 3.1415)) as i32;
+                let Q = 8192 - (ctrl >> 4) * (7000/15);
+                let Qlimit = (8192*4096/F - F/2) * 3 / 4;
+                if Q > Qlimit {
+                    Q = Qlimit;
+                }
                 let low_out = ctrl & 1;
                 let high_out = (ctrl >> 1) & 1;
                 let band_out = (ctrl >> 2) & 1;
@@ -152,3 +172,9 @@ export fn gesSnd(t: i32) -> f32 {
     }
     (((t & 127) * 4)!GesBufferOffset) as f32 / 32768 as f32
 }
+
+fn polyBlep(transientPhase: i32, invPhaseInc: f32, magnitude: i32) -> i32 {
+    let lazy t = ((transientPhase << 16) >> 16) as f32 * invPhaseInc;
+    let lazy x = max(0 as f32, 1 as f32 - abs(t));
+    (f32.copysign(x * x, t) * magnitude as f32) as i32
+}

platform/src/ges_only.cwa

@@ -0,0 +1,5 @@
+import "env.memory" memory(1);
+import "env.sin" fn sin(f32) -> f32;
+import "env.pow" fn pow(f32, f32) -> f32;
+
+include "ges.cwa"

src/run-web.html

@@ -1 +1 @@
-<!doctype html><html><head><meta charset="utf8"><title>uw8-run</title><style>body,canvas,html{background-color:#202024;margin:0;padding:0}body,html{height:100%}body{display:grid;grid-template-rows:1fr}#screen{align-self:center;border:4px solid #303040;image-rendering:pixelated;justify-self:center}#message{background-color:rgba(0,0,0,.4);color:#c64;font:700 12pt sans-serif;padding:8px;position:absolute;width:calc(100% - 16px);z-index:2}@media (min-width:648px) and (min-height:488px){#screen{height:480px;width:640px}}@media (min-width:968px) and (min-height:728px){#screen{height:720px;width:960px}}</style></head><body> <canvas id="screen" width="320" height="240" tabindex="1"> </canvas> <div id="message"></div> </body><script type="module">function e(e){return e&&e.__esModule?e.default:e}class t extends AudioWorkletNode{constructor(e){super(e,"apu",{outputChannelCount:[2]})}}let A=(...e)=>new Uint8Array(...e),a=(...e)=>new Uint32Array(...e);let 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c.audioWorklet.addModule(e("data:application/javascript,let%20e%3D%28...e%29%3D%3Enew%20Uint8Array%28...e%29%3Bclass%20s%20extends%20AudioWorkletProcessor%7Bconstructor%28%29%7Bsuper%28%29%2Cthis.sampleIndex%3D0%2Cthis.port.onmessage%3Ds%3D%3E%7Bthis.memory%3Fe%28this.memory.buffer%2C80%2C32%29.set%28e%28s.data%29%29%3Athis.load%28s.data%5B0%5D%2Cs.data%5B1%5D%29%7D%7Dasync%20load%28e%2Cs%29%7Blet%20t%3Dnew%20WebAssembly.Memory%28%7Binitial%3A4%2Cmaximum%3A4%7D%29%2Ca%3D%7Benv%3A%7Bmemory%3At%7D%7D%3Bfor%28let%20e%20of%5B%22acos%22%2C%22asin%22%2C%22atan%22%2C%22atan2%22%2C%22cos%22%2C%22exp%22%2C%22log%22%2C%22sin%22%2C%22tan%22%2C%22pow%22%5D%29a.env%5Be%5D%3DMath%5Be%5D%3Bfor%28let%20e%3D9%3Be%3C64%3B%2B%2Be%29a.env%5B%22reserved%22%2Be%5D%3D%28%29%3D%3E%7B%7D%3Bfor%28let%20e%3D0%3Be%3C16%3B%2B%2Be%29a.env%5B%22g_reserved%22%2Be%5D%3D0%3Blet%20r%3Dasync%20e%3D%3E%28await%20WebAssembly.instantiate%28e%2Ca%29%29.instance%2Cn%3Dawait%20r%28e%29%3Bfor%28let%20e%20in%20n.exports%29a.env%5Be%5D%3Dn.exports%5Be%5D%3Blet%20o%3Dawait%20r%28s%29%3Bthis.memory%3Dt%2Cthis.snd%3Do.exports.snd%7C%7Cn.exports.gesSnd%2Cthis.port.postMessage%282%29%7Dprocess%28e%2Cs%2Ct%29%7Bif%28this.snd%29%7Blet%20e%3Ds%5B0%5D%2Ct%3Dthis.sampleIndex%2Ca%3De%5B0%5D.length%3Bfor%28let%20s%3D0%3Bs%3Ca%3B%2B%2Bs%29e%5B0%5D%5Bs%5D%3Dthis.snd%28t%2B%2B%29%2Ce%5B1%5D%5Bs%5D%3Dthis.snd%28t%2B%2B%29%3Bthis.sampleIndex%3D4294967295%26t%7Dreturn%210%7D%7DregisterProcessor%28%22apu%22%2Cs%29%3B"));let f,E=new t(c),C=0,I=new Promise((e=>f=e)),p=e=>{C|=e,3==C&&f&&(f(!0),f=null)};E.port.onmessage=e=>p(e.data);let y=()=>{"suspended"==c.state?(n.startButton&&(n.startButton.style="",B.style="display:none"),(n.startButton||B).onclick=()=>{c.resume()}):(n.startButton&&(n.startButton.style="display:none",B.style=""),p(1))};c.onstatechange=y,y(),o=r;let w=window.location.pathname;if(Q<=1024&&!i){let e="";for(let t of A(r))e+=String.fromCharCode(t);w+="#"+btoa(e),w!=window.location.pathname+window.location.hash&&history.pushState(null,null,w)}B.width=B.width;try{let t={initial:4};g||(t.maximum=4);let B,s=new WebAssembly.Memory(t),i=A(s.buffer),f={env:{memory:s}},C=e=>{if(B&&(!g||0!=A(e)[0])){i.set(A(e));let t=B.exports.load_uw8(e.byteLength);e=new ArrayBuffer(t),A(e).set(i.slice(0,t))}return e},p=async e=>(await WebAssembly.instantiate(e,f)).instance,y=async e=>C(await(await fetch(e)).arrayBuffer());B=await p(await 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+<!doctype html><html><head><meta charset="utf8"><title>uw8-run</title><style>body,canvas,html{background-color:#202024;margin:0;padding:0}body,html{height:100%}body{display:grid;grid-template-rows:1fr}#screen{align-self:center;border:4px solid #303040;image-rendering:pixelated;justify-self:center}#message{background-color:rgba(0,0,0,.4);color:#c64;font:700 12pt sans-serif;padding:8px;position:absolute;width:calc(100% - 16px);z-index:2}@media (min-width:648px) and (min-height:488px){#screen{height:480px;width:640px}}@media (min-width:968px) and (min-height:728px){#screen{height:720px;width:960px}}</style></head><body> <canvas id="screen" width="320" height="240" tabindex="1"> </canvas> <div id="message"></div> </body><script type="module">function e(e){return e&&e.__esModule?e.default:e}class t extends AudioWorkletNode{constructor(e){super(e,"apu",{outputChannelCount:[2]})}}let A=(...e)=>new Uint8Array(...e),a=(...e)=>new Uint32Array(...e);let B=function(B,n={}){n.setMessage||(n.setMessage=(e,t)=>{t&&console.log("error: "+t)});let o,s,r,i,F=B.getContext("2d"),l=F.createImageData(320,240),d=n.devkitMode,c=0,Q=null==n.keyboardElement?B:n.keyboardElement;if(Q){let e=e=>{let t,A="keydown"==e.type;switch(e.code){case"ArrowUp":t=1;break;case"ArrowDown":t=2;break;case"ArrowLeft":t=4;break;case"ArrowRight":t=8;break;case"KeyZ":t=16;break;case"KeyX":t=32;break;case"KeyA":t=64;break;case"KeyS":t=128;break;case"KeyR":A&&C(s,!0);break;case"F9":A&&B.toBlob((e=>{g(e,".png")})),e.preventDefault();break;case"F10":A&&function(){if(r)return r.stop(),void(r=null);r=new MediaRecorder(B.captureStream(),{mimeType:"video/webm",videoBitsPerSecond:25e6});let e=[];r.ondataavailable=t=>{e.push(t.data)};let t=n.timerElement;t&&(t.hidden=!1,t.innerText="00:00");function A(){if(i){if(t){let e=Math.floor((Date.now()-i)/1e3);t.innerText=Math.floor(e/60).toString().padStart(2,"0")+":"+(e%60).toString().padStart(2,"0")}setTimeout(A,1e3)}}r.onstop=()=>{t&&(t.hidden=!0),g(new Blob(e,{type:"video/webm"}),".webm")},r.start(),i=Date.now(),setTimeout(A,1e3)}(),e.preventDefault()}A?c|=t:c&=~t};Q.onkeydown=e,Q.onkeyup=e}async function C(r,i){o&&(o(),o=null);let Q=new AudioContext({sampleRate:44100}),g=!0;o=()=>{Q.close(),g=!1};let w=r.byteLength;if(n.setMessage(w),0==w)return;await Q.audioWorklet.addModule(e("data:application/javascript,let%20e%3D%28...e%29%3D%3Enew%20Uint8Array%28...e%29%3Bclass%20s%20extends%20AudioWorkletProcessor%7Bconstructor%28%29%7Bsuper%28%29%2Cthis.sampleIndex%3D0%2Cthis.port.onmessage%3Ds%3D%3E%7Bthis.memory%3Fe%28this.memory.buffer%2C80%2C32%29.set%28e%28s.data%29%29%3Athis.load%28s.data%5B0%5D%2Cs.data%5B1%5D%29%7D%7Dasync%20load%28e%2Cs%29%7Blet%20t%3Dnew%20WebAssembly.Memory%28%7Binitial%3A4%2Cmaximum%3A4%7D%29%2Ca%3D%7Benv%3A%7Bmemory%3At%7D%7D%3Bfor%28let%20e%20of%5B%22acos%22%2C%22asin%22%2C%22atan%22%2C%22atan2%22%2C%22cos%22%2C%22exp%22%2C%22log%22%2C%22sin%22%2C%22tan%22%2C%22pow%22%5D%29a.env%5Be%5D%3DMath%5Be%5D%3Bfor%28let%20e%3D9%3Be%3C64%3B%2B%2Be%29a.env%5B%22reserved%22%2Be%5D%3D%28%29%3D%3E%7B%7D%3Bfor%28let%20e%3D0%3Be%3C16%3B%2B%2Be%29a.env%5B%22g_reserved%22%2Be%5D%3D0%3Blet%20r%3Dasync%20e%3D%3E%28await%20WebAssembly.instantiate%28e%2Ca%29%29.instance%2Cn%3Dawait%20r%28e%29%3Bfor%28let%20e%20in%20n.exports%29a.env%5Be%5D%3Dn.exports%5Be%5D%3Blet%20o%3Dawait%20r%28s%29%3Bthis.memory%3Dt%2Cthis.snd%3Do.exports.snd%7C%7Cn.exports.gesSnd%2Cthis.port.postMessage%282%29%7Dprocess%28e%2Cs%2Ct%29%7Bif%28this.snd%29%7Blet%20e%3Ds%5B0%5D%2Ct%3Dthis.sampleIndex%2Ca%3De%5B0%5D.length%3Bfor%28let%20s%3D0%3Bs%3Ca%3B%2B%2Bs%29e%5B0%5D%5Bs%5D%3Dthis.snd%28t%2B%2B%29%2Ce%5B1%5D%5Bs%5D%3Dthis.snd%28t%2B%2B%29%3Bthis.sampleIndex%3D4294967295%26t%7Dreturn%210%7D%7DregisterProcessor%28%22apu%22%2Cs%29%3B"));let u,f=new t(Q),D=0,p=new Promise((e=>u=e)),E=e=>{D|=e,3==D&&u&&(u(!0),u=null)};f.port.onmessage=e=>E(e.data);let I=()=>{"suspended"==Q.state?(n.startButton&&(n.startButton.style="",B.style="display:none"),(n.startButton||B).onclick=()=>{Q.resume()}):(n.startButton&&(n.startButton.style="display:none",B.style=""),E(1))};Q.onstatechange=I,I(),s=r;let m=window.location.pathname;if(w<=1024&&!i){let e="";for(let t of A(r))e+=String.fromCharCode(t);m+="#"+btoa(e),m!=window.location.pathname+window.location.hash&&history.pushState(null,null,m)}B.width=B.width;try{let t={initial:4};d||(t.maximum=4);let B,o=new WebAssembly.Memory(t),i=A(o.buffer),u={env:{memory:o}},D=e=>{if(B&&(!d||0!=A(e)[0])){i.set(A(e));let t=B.exports.load_uw8(e.byteLength);e=new ArrayBuffer(t),A(e).set(i.slice(0,t))}return e},E=async e=>(await WebAssembly.instantiate(e,u)).instance,I=async e=>D(await(await fetch(e)).arrayBuffer());B=await E(await 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test/ges_test.cwa

@@ -0,0 +1,30 @@
+import "env.memory" memory(4);
+import "env.pow" fn pow(f32, f32) -> f32;
+import "env.sin" fn sin(f32) -> f32;
+import "env.cls" fn cls(i32);
+import "env.rectangle" fn rectangle(f32, f32, f32, f32, i32);
+
+include "../platform/src/ges.cwa"
+
+export fn snd(t: i32) -> f32 {
+    gesSnd(t)
+}
+
+export fn upd() {
+    80?0 = 32!32 / 200 & 2 | 0x41;
+    80?3 = (32!32 / 400)%7*12/7 + 40;
+    let pulse = (32!32 * 256 / 2000) & 511;
+    if pulse >= 256 {
+        pulse = 511 - pulse;
+    }
+    80?1 = pulse;
+
+    cls(0);
+    rectangle(0.0, 100.0, (pulse * 320 / 256) as f32, 16.0, 15);
+}
+
+data 80 {
+    i8(
+        0x41, 0, 0, 80, 0x70, 0
+    )
+}

tests/plot_ges.cwa

@@ -0,0 +1,59 @@
+include "../examples/include/microw8-api.cwa"
+
+export fn upd() {
+    80?0 = (32!32 >> 11 << 6) | 5;
+    80?1 = (sin(time() * 6 as f32) * 95 as f32) as i32 + 128;
+    plotGes();
+}
+
+data 80 { i8 (
+    1, 128, 0, 69, 0, 15,
+    0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0,
+    0xff, 0xff,
+    0xc1, 0, 0, 110, 0, 0
+) }
+
+//import "env.gesSnd" fn gesSnd(i32) -> f32;
+
+include "../platform/src/ges.cwa"
+
+export fn snd(t: i32) -> f32 {
+    gesSnd(t)
+}
+
+global mut samplePos: i32 = 0;
+
+const SoundBuffer = 0x30000;
+
+fn plotGes() {
+    rectangle(0 as f32, 10 as f32, 320 as f32, 320 as f32, 0);
+    let count = (time() * 44100 as f32) as i32 * 2 - samplePos;
+    let i: i32;
+    loop genLoop {
+        (i*4)$SoundBuffer = gesSnd(samplePos + i);
+        branch_if (i := i + 1) < count: genLoop;
+    }
+    samplePos = samplePos + count;
+
+    let ch: i32;
+    loop channelLoop {
+        let offset = 159;
+        i = 0;
+
+        loop searchLoop {
+            offset = offset + 1;
+            branch_if (offset * 8 + ch - 8)$SoundBuffer < 0 as f32 | (offset * 8 + ch)$SoundBuffer >= 0 as f32 & offset + 160 < count: searchLoop;
+        }
+
+        offset = ch + (offset - 160) * 8;
+        i = 0;
+        loop plotLoop {
+            setPixel(i, floor((i * 8 + offset)$SoundBuffer * 127 as f32) as i32 + 60 + ch * (120/8), 15);
+            branch_if (i := i + 1) < 320: plotLoop;
+        }
+
+        branch_if (ch := ch + 8) < 16: channelLoop;
+    }
+}