Add dsp::convert().

include/dsp/convert.hpp

@@ -0,0 +1,65 @@
+#pragma once
+#include <type_traits>
+#include <dsp/common.hpp>
+
+
+namespace rack {
+namespace dsp {
+
+
+/** 24-bit integer, using int32_t for conversions. */
+struct __attribute__((packed)) int24_t {
+	int32_t i : 24;
+	int24_t(int32_t i) : i(i) {}
+	operator int32_t() {return i;}
+};
+static_assert(sizeof(int24_t) == 3, "int24_t type must be 3 bytes");
+
+
+/** Converts between normalized types */
+template <typename To, typename From>
+To convert(From x);
+
+
+/** Trivial conversion */
+template <typename To>
+To convert(To x) {return x;}
+
+
+/** Integer to float */
+template <>
+inline float convert(int8_t x) {return x / 128.f;}
+template <>
+inline float convert(int16_t x) {return x / 32768.f;}
+template <>
+inline float convert(int24_t x) {return x / 8388608.f;}
+template <>
+inline float convert(int32_t x) {return x / 2147483648.f;}
+template <>
+inline float convert(int64_t x) {return x / 9223372036854775808.f;}
+
+
+/** Float to integer */
+template <>
+inline int8_t convert(float x) {return std::min(std::llround(x * 128.f), 127LL);}
+template <>
+inline int16_t convert(float x) {return std::min(std::llround(x * 32768.f), 32767LL);}
+template <>
+inline int24_t convert(float x) {return std::min(std::llround(x * 8388608.f), 8388607LL);}
+template <>
+inline int32_t convert(float x) {return std::min(std::llround(x * 2147483648.f), 2147483647LL);}
+template <>
+inline int64_t convert(float x) {return std::min(std::llround(x * 9223372036854775808.f), 9223372036854775807LL);}
+
+
+/** Buffer conversion */
+template <typename To, typename From>
+void convert(const From* in, To* out, size_t len) {
+	for (size_t i = 0; i < len; i++) {
+		out[i] = convert<To, From>(in[i]);
+	}
+}
+
+
+} // namespace dsp
+} // namespace rack

include/rack.hpp

@@ -94,6 +94,7 @@ Directly including Rack headers other than rack.hpp in your plugin is unsupporte
 #include <plugin/Model.hpp>
 #include <plugin/callbacks.hpp>
 
+#include <dsp/common.hpp>
 #include <dsp/window.hpp>
 #include <dsp/ode.hpp>
 #include <dsp/minblep.hpp>
@@ -106,7 +107,7 @@ Directly including Rack headers other than rack.hpp in your plugin is unsupporte
 #include <dsp/vumeter.hpp>
 #include <dsp/filter.hpp>
 #include <dsp/digital.hpp>
-#include <dsp/common.hpp>
+#include <dsp/convert.hpp>
 
 #include <simd/Vector.hpp>
 #include <simd/functions.hpp>