feat: 3D relief, lighting and reactive motion

The spectrogram now extrudes the geometry alongside the waveform, the skin is lit with a screen-space normal, and the sphere tumbles and pulses with the kick and signal energy.
2026-05-18 18:39:14 +02:00
parent e33375f7ac
commit 7fc4f41f4e
6 changed files with 60 additions and 14 deletions
@@ -5,7 +5,9 @@ uniform float scrollOffset;
 uniform int   colormapId;
 uniform int   renderMode;       // 0 = skin, 1 = points

-in vec2 vSphereUV;
+in vec2  vSphereUV;
+in vec3  vViewPos;
+in float vWave;
 out vec4 fragColor;

 // Polynomial colormap fits (public domain, Matt Zucker).
@@ -34,9 +36,24 @@ void main() {
    float u = fract(vSphereUV.x - scrollOffset);
    float mag = clamp(texture(spectroTex, vec2(u, vSphereUV.y)).r, 0.0, 1.0);
    vec3 col = (colormapId == 0) ? magma(mag) : viridis(mag);
+
    if (renderMode == 1) {
+        // round point sprites + a touch of waveform sheen
        vec2 d = gl_PointCoord - vec2(0.5);
-        if (dot(d, d) > 0.25) discard;       // round the points
+        if (dot(d, d) > 0.25) discard;
+        col += 0.20 * abs(vWave);
+        fragColor = vec4(col, 1.0);
+        return;
    }
-    fragColor = vec4(col, 1.0);
+
+    // skin: light the displaced relief with a screen-space face normal
+    vec3 N = normalize(cross(dFdx(vViewPos), dFdy(vViewPos)));
+    vec3 V = normalize(-vViewPos);
+    if (dot(N, V) < 0.0) N = -N;
+    vec3  L    = normalize(vec3(0.45, 0.65, 0.75));
+    float diff = max(dot(N, L), 0.0);
+    float rim  = pow(1.0 - max(dot(N, V), 0.0), 2.5);
+
+    vec3 lit = col * (0.35 + 0.85 * diff) + rim * vec3(0.35, 0.45, 0.65);
+    fragColor = vec4(lit, 1.0);
 }
@@ -1,14 +1,20 @@
 #version 150

 uniform mat4 modelViewProjectionMatrix;
-uniform sampler2D waveformTex;   // width = samples, height = 2 (row0 CH1, row1 CH2)
+uniform mat4 modelViewMatrix;
+uniform sampler2D waveformTex;
+uniform sampler2D spectroTex;
 uniform float displaceAmount;
+uniform float spectroAmount;
+uniform float scrollOffset;
 uniform float baseRadius;
 uniform int   renderMode;        // 0 = skin, 1 = points

 in vec4 position;

-out vec2 vSphereUV;   // x = longitude [0,1], y = latitude [0,1]
+out vec2  vSphereUV;
+out vec3  vViewPos;
+out float vWave;

 const float PI = 3.14159265359;

@@ -17,14 +23,22 @@ void main() {
    float lon = atan(dir.z, dir.x) / (2.0 * PI) + 0.5;
    float lat = asin(clamp(dir.y, -1.0, 1.0)) / PI + 0.5;

+    // waveform ripple (per hemisphere) + scrolling spectrogram relief
    float row  = (dir.y >= 0.0) ? 0.25 : 0.75;          // CH1 north, CH2 south
-    float wave = texture(waveformTex, vec2(lon, row)).r; // [-1,1]
-    float r    = baseRadius * (1.0 + displaceAmount * wave);
+    float wave = texture(waveformTex, vec2(lon, row)).r;             // [-1,1]
+    float spec = texture(spectroTex,
+                         vec2(fract(lon - scrollOffset), lat)).r;    // [0,1]
+
+    float r = baseRadius * (1.0 + displaceAmount * wave
+                                + spectroAmount * spec);
    if (renderMode == 1) {
-        r *= 1.05;            // float the point cloud just outside the skin
+        r *= 1.06;                  // float the point cloud outside the skin
        gl_PointSize = 6.0;
    }

-    gl_Position = modelViewProjectionMatrix * vec4(dir * r, 1.0);
+    vec4 viewPos = modelViewMatrix * vec4(dir * r, 1.0);
+    gl_Position  = modelViewProjectionMatrix * vec4(dir * r, 1.0);
+    vViewPos  = viewPos.xyz;
    vSphereUV = vec2(lon, lat);
+    vWave     = wave;
 }
@@ -78,6 +78,7 @@ void SphereViz::bindUniforms() {
    shader_.setUniformTexture("waveformTex", waveTex_, 1);
    shader_.setUniform1f("scrollOffset", scrollOffset_);
    shader_.setUniform1f("displaceAmount", displace_);
+    shader_.setUniform1f("spectroAmount", spectroAmount_);
    shader_.setUniform1f("baseRadius", baseRadius_);
    shader_.setUniform1i("colormapId", colormapId_);
 }
@@ -35,6 +35,7 @@ private:
    int   waveformLen_ = 0;
    float baseRadius_  = 200.0f;
    float scrollOffset_ = 0.0f;
-    float displace_    = 0.18f;
+    float displace_     = 0.28f;
+    float spectroAmount_ = 0.40f;
    int   colormapId_  = 0;
 };
@@ -1,4 +1,6 @@
 #include "ofApp.h"
+#include <algorithm>
+#include <cmath>

 void ofApp::setup() {
    ofSetFrameRate(60);
@@ -30,10 +32,6 @@ void ofApp::setup() {
 void ofApp::update() {
    if (frozen_) return;

-    // Auto-rotation advances only when the mouse is not orbiting the camera.
-    if (!ofGetMousePressed())
-        spin_ += 6.0f * static_cast<float>(ofGetLastFrameTime());
-
    if (demoMode_) {
        demo_.next(buf1_, buf2_, 8192);
    } else {
@@ -48,6 +46,17 @@ void ofApp::update() {
    analyzerCh1_.update(buf1_, buf1_, sr);
    analyzerCh2_.update(buf2_, buf2_, sr);

+    // Audio-reactive motion: rotation speed tracks signal energy, the whole
+    // sphere pulses with the kick transient.
+    const oscope::AudioBands& b1 = analyzerCh1_.bands();
+    const oscope::AudioBands& b2 = analyzerCh2_.bands();
+    const float energy = 0.5f * (b1.full + b2.full);
+    const float kick   = std::max(b1.kick, b2.kick);
+    const float dt     = static_cast<float>(ofGetLastFrameTime());
+    if (!ofGetMousePressed())
+        spin_ += (8.0f + 80.0f * energy) * dt;
+    pulse_ += (1.0f + 0.20f * kick - pulse_) * 0.25f;
+
    sphere_.setColormap(colormap_);
    sphere_.pushSpectrogramColumn(analyzerCh1_.magDown(),
                                  analyzerCh2_.magDown());
@@ -56,9 +65,12 @@ void ofApp::update() {
 }

 void ofApp::draw() {
+    const float t = ofGetElapsedTimef();
    cam_.begin();
    ofPushMatrix();
    ofRotateYDeg(spin_);
+    ofRotateXDeg(16.0f * std::sin(t * 0.27f));   // slow tumble
+    ofScale(pulse_, pulse_, pulse_);             // audio pulse
    if (layerA_) sphere_.drawSkin();
    if (layerC_) sphere_.drawPoints();
    if (layerB_) rings_.draw();
@@ -38,5 +38,6 @@ private:
    int   colormap_ = 0;
    float scopeSr_  = 16.0e6f;
    float spin_     = 0.0f;
+    float pulse_    = 1.0f;
    std::string statusText_;
 };