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Adds a test for lookup sine. And fixes lookup sine.

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This commit is contained in:
Thomas Harte 2020-04-20 18:40:47 -04:00
parent 6568c29c54
commit 99fa86a67e
2 changed files with 56 additions and 6 deletions
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2
Components/OPL2/Implementation/Tables.hpp
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@ -82,7 +82,7 @@ constexpr LogSign negative_log_sin(int x) {
constexpr int16_t mask[] = { 0, 255 };
return {
.log = log_sin[x & 255] ^ mask[(x >> 8) & 1],
.log = log_sin[(x & 255) ^ mask[(x >> 8) & 1]],
.sign = sign[(x >> 9) & 1]
};
}

60
OSBindings/Mac/Clock SignalTests/OPLTests.mm
View File

@ -9,6 +9,7 @@
#import <XCTest/XCTest.h>
#include "OPL2.hpp"
#include <cmath>
@interface OPLTests: XCTestCase
@end
@ -16,6 +17,18 @@
@implementation OPLTests {
}
- (void)testSineLookup {
for(int c = 0; c < 1024; ++c) {
const auto logSin = Yamaha::OPL::negative_log_sin(c);
const auto level = Yamaha::OPL::power_two(logSin);
double fl_angle = double(c) * M_PI / 512.0;
double fl_level = sin(fl_angle);
XCTAssertLessThanOrEqual(fabs(fl_level - double(level) / 4096.0), 0.01, "Sine varies by more than 0.01 at angle %d", c);
}
}
- (void)testADSR {
Yamaha::OPL::Operator test_operator;
Yamaha::OPL::OperatorState test_state;
@ -23,18 +36,55 @@
test_operator.set_attack_decay(0x88);
test_operator.set_sustain_release(0x88);
// While key is off, ADSR attenuation should remain above 511.
// While key is off, output level should remain at 0.
for(int c = 0; c < 1024; ++c) {
test_operator.update(test_state, false, 0, 0);
XCTAssertGreaterThanOrEqual(test_state.attenuation, 511);
test_operator.update(test_state, false, 0, 0, 0);
XCTAssertGreaterThanOrEqual(test_state.level(), 0);
}
// Set key on...
for(int c = 0; c < 4096; ++c) {
test_operator.update(test_state, true, 0, 0);
NSLog(@"%d", test_state.attenuation);
test_operator.update(test_state, true, 0, 0, 0);
NSLog(@"%d", test_state.level());
}
}
- (void)testFM {
Yamaha::OPL::Operator modulator, carrier;
Yamaha::OPL::Channel channel;
// Set: AM = 0, PM = 0, EG = 1, KR = 0, MUL = 0
modulator.set_am_vibrato_hold_sustain_ksr_multiple(0x20);
carrier.set_am_vibrato_hold_sustain_ksr_multiple(0x20);
// Set: KL = 0, TL = 0
modulator.set_scaling_output(0x3f);
carrier.set_scaling_output(0);
// Set: waveform = 0.
modulator.set_waveform(0);
carrier.set_waveform(0);
// Set FB = 0, use FM synthesis.
channel.set_feedback_mode(1);
// Set: AR = 15, DR = 0.
modulator.set_attack_decay(0xf0);
carrier.set_attack_decay(0xf0);
// Set: SL = 0, RR = 15.
modulator.set_sustain_release(0x0f);
carrier.set_sustain_release(0x0f);
// Set 16384 samples for 1 period, and key-on.
channel.set_frequency_low(0x40);
channel.set_9bit_frequency_octave_key_on(0x10);
// Grab a bunch of samples.
for(int c = 0; c < 16384; ++c) {
printf("%d\n", channel.update(&modulator, &carrier));
}
printf("\n");
}
@end