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Merge pull request #699 from system64MC/wavetable_interpolation_no_opf2

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Wavetable interpolation
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tildearrow 2022-10-12 14:26:43 -05:00 committed by GitHub
parent 843d18290d 0782e3af1d
commit 8be5e5a9e6
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GPG key ID: 4AEE18F83AFDEB23
3 changed files with 77 additions and 9 deletions
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1
src/gui/gui.cpp
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@ -5608,6 +5608,7 @@ FurnaceGUI::FurnaceGUI():
#endif #endif
hasACED(false), hasACED(false),
waveGenBaseShape(0), waveGenBaseShape(0),
waveInterpolation(0),
waveGenDuty(0.5f), waveGenDuty(0.5f),
waveGenPower(1), waveGenPower(1),
waveGenInvertPoint(1.0f), waveGenInvertPoint(1.0f),

1
src/gui/gui.h
View file

@ -1615,6 +1615,7 @@ class FurnaceGUI {
// wave generator // wave generator
int waveGenBaseShape; int waveGenBaseShape;
int waveInterpolation;
float waveGenDuty; float waveGenDuty;
int waveGenPower; int waveGenPower;
float waveGenInvertPoint; float waveGenInvertPoint;

84
src/gui/waveEdit.cpp
View file

@ -33,6 +33,13 @@ const char* waveGenBaseShapes[4]={
"Pulse" "Pulse"
}; };
const char* waveInterpolations[4] = {
"None",
"Linear",
"Cosine",
"Cubic"
};
const float multFactors[17]={ const float multFactors[17]={
M_PI, M_PI,
2*M_PI, 2*M_PI,
@ -555,17 +562,76 @@ void FurnaceGUI::drawWaveEdit() {
if (waveGenScaleX<2) waveGenScaleX=2; if (waveGenScaleX<2) waveGenScaleX=2;
if (waveGenScaleX>256) waveGenScaleX=256; if (waveGenScaleX>256) waveGenScaleX=256;
} }
ImGui::SetNextItemWidth(ImGui::GetContentRegionAvail().x);
if (CWSliderInt("##WGInterpolation", &waveInterpolation, 0, 3, waveInterpolations[waveInterpolation])) {
if (waveInterpolation < 0) waveInterpolation = 0;
if (waveInterpolation > 3) waveInterpolation = 3;
//doGenerateWave();
}
ImGui::TableNextColumn(); ImGui::TableNextColumn();
if (ImGui::Button("Scale X")) { if (ImGui::Button("Scale X")) {
if (waveGenScaleX>0 && wave->len!=waveGenScaleX) e->lockEngine([this,wave]() { if (waveGenScaleX > 0 && wave->len != waveGenScaleX) e->lockEngine([this, wave]() {
int origData[256]; int origData[256];
memcpy(origData,wave->data,wave->len*sizeof(int)); // Copy original wave to temp buffer
for (int i=0; i<waveGenScaleX; i++) { // If longer than 256 samples, return
wave->data[i]=origData[i*wave->len/waveGenScaleX]; if (wave->len > 256)
} {
wave->len=waveGenScaleX; showError("ERROR : Wavetable longer than 256 samples!");
MARK_MODIFIED; return;
}); }
memcpy(origData, wave->data, wave->len * sizeof(int));
float t = 0; // Index used into `origData`
for (int i = 0; i < waveGenScaleX; i++, t += (float)wave->len / waveGenScaleX) {
switch (waveInterpolation)
{
default: // No interpolation
{
wave->data[i] = origData[i * wave->len / waveGenScaleX];
break; // No interpolation
}
case 0:
{
wave->data[i] = origData[i * wave->len / waveGenScaleX];
break;
}
case 1: // Linear
{
int idx = t; // Implicitly floors `t`
int s0 = origData[(idx) % wave->len], s1 = origData[(idx + 1) % wave->len];
double mu = (t - idx);
wave->data[i] = s0 + mu * s1 - (mu * s0);
break;
}
case 2: // Cosine
{
int idx = t; // Implicitly floors `t`
int s0 = origData[(idx) % wave->len], s1 = origData[(idx + 1) % wave->len];
double mu = (t - idx);
double muCos = (1 - cos(mu * M_PI)) / 2;
wave->data[i] = s0 + muCos * s1 - (muCos * s0);
break;
}
case 3: // Cubic Spline
{
int idx = t; // Implicitly floors `t`
int s0 = origData[((idx - 1 % wave->len + wave->len) % wave->len)], s1 = origData[(idx) % wave->len], s2 = origData[(idx + 1) % wave->len], s3 = origData[(idx + 2) % wave->len];
double a0, a1, a2, a3;
double mu = (t - idx);
double mu2 = mu * mu;
a0 = -0.5 * s0 + 1.5 * s1 - 1.5 * s2 + 0.5 * s3;
a1 = s0 - 2.5 * s1 + 2 * s2 - 0.5 * s3;
a2 = -0.5 * s0 + 0.5 * s2;
a3 = s1;
wave->data[i] = (a0 * mu * mu2 + a1 * mu2 + a2 * mu + a3);
}
}
}
wave->len = waveGenScaleX;
MARK_MODIFIED;
});
} }
ImGui::TableNextRow(); ImGui::TableNextRow();