Update residfp to newer build

Co-Authored-By: Alexander Babikov <2708460+lemondrops@users.noreply.github.com>

src/sound/resid-fp/WaveformCalculator.h

@@ -0,0 +1,136 @@
+/*
+ * This file is part of libsidplayfp, a SID player engine.
+ *
+ * Copyright 2011-2023 Leandro Nini <drfiemost@users.sourceforge.net>
+ * Copyright 2007-2010 Antti Lankila
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#ifndef WAVEFORMCALCULATOR_h
+#define WAVEFORMCALCULATOR_h
+
+#include <map>
+
+#include "array.h"
+#include "sidcxx11.h"
+#include "siddefs-fp.h"
+
+
+namespace reSIDfp
+{
+
+/**
+ * Combined waveform model parameters.
+ */
+typedef struct
+{
+    float threshold;
+    float pulsestrength;
+    float distance1;
+    float distance2;
+} CombinedWaveformConfig;
+
+/**
+ * Combined waveform calculator for WaveformGenerator.
+ * By combining waveforms, the bits of each waveform are effectively short
+ * circuited. A zero bit in one waveform will result in a zero output bit
+ * (thus the infamous claim that the waveforms are AND'ed).
+ * However, a zero bit in one waveform may also affect the neighboring bits
+ * in the output.
+ *
+ * Example:
+ * 
+ *                 1 1
+ *     Bit #       1 0 9 8 7 6 5 4 3 2 1 0
+ *                 -----------------------
+ *     Sawtooth    0 0 0 1 1 1 1 1 1 0 0 0
+ *     
+ *     Triangle    0 0 1 1 1 1 1 1 0 0 0 0
+ *     
+ *     AND         0 0 0 1 1 1 1 1 0 0 0 0
+ *     
+ *     Output      0 0 0 0 1 1 1 0 0 0 0 0
+ *
+ *
+ * Re-vectorized die photographs reveal the mechanism behind this behavior.
+ * Each waveform selector bit acts as a switch, which directly connects
+ * internal outputs into the waveform DAC inputs as follows:
+ *
+ * - Noise outputs the shift register bits to DAC inputs as described above.
+ *   Each output is also used as input to the next bit when the shift register
+ *   is shifted. Lower four bits are grounded.
+ * - Pulse connects a single line to all DAC inputs. The line is connected to
+ *   either 5V (pulse on) or 0V (pulse off) at bit 11, and ends at bit 0.
+ * - Triangle connects the upper 11 bits of the (MSB EOR'ed) accumulator to the
+ *   DAC inputs, so that DAC bit 0 = 0, DAC bit n = accumulator bit n - 1.
+ * - Sawtooth connects the upper 12 bits of the accumulator to the DAC inputs,
+ *   so that DAC bit n = accumulator bit n. Sawtooth blocks out the MSB from
+ *   the EOR used to generate the triangle waveform.
+ *
+ * We can thus draw the following conclusions:
+ *
+ * - The shift register may be written to by combined waveforms.
+ * - The pulse waveform interconnects all bits in combined waveforms via the
+ *   pulse line.
+ * - The combination of triangle and sawtooth interconnects neighboring bits
+ *   of the sawtooth waveform.
+ *
+ * Also in the 6581 the MSB of the oscillator, used as input for the
+ * triangle xor logic and the pulse adder's last bit, is connected directly
+ * to the waveform selector, while in the 8580 it is latched at sid_clk2
+ * before being forwarded to the selector. Thus in the 6581 if the sawtooth MSB
+ * is pulled down it might affect the oscillator's adder
+ * driving the top bit low.
+ *
+ */
+class WaveformCalculator
+{
+private:
+    typedef std::map<const CombinedWaveformConfig*, matrix_t> cw_cache_t;
+
+private:
+    matrix_t wftable;
+
+    cw_cache_t PULLDOWN_CACHE;
+
+private:
+    WaveformCalculator();
+
+public:
+    /**
+     * Get the singleton instance.
+     */
+    static WaveformCalculator* getInstance();
+
+    /**
+     * Get the waveform table for use by WaveformGenerator.
+     *
+     * @return Waveform table
+     */
+    matrix_t* getWaveTable() { return &wftable; }
+
+    /**
+     * Build pulldown table for use by WaveformGenerator.
+     *
+     * @param model Chip model to use
+     * @return Pulldown table
+     */
+    matrix_t* buildPulldownTable(ChipModel model);
+};
+
+} // namespace reSIDfp
+
+#endif