Replace make_tables by C++11 constexpr arrays

.azure/azure-pipelines-alpine.yml

@@ -33,6 +33,7 @@ stages:
       vmImage: 'ubuntu-24.04'
     steps:
     - checkout: self
+      submodules: true
 
     - task: Docker@2
       continueOnError: true
@@ -87,6 +88,7 @@ stages:
       container: alpine-linux
       steps:
       - checkout: self
+        submodules: true
       - task: CMake@1
         displayName: 'CMake configure'
         inputs:

.azure/azure-pipelines-android.yml

@@ -127,6 +127,9 @@ jobs:
     vmImage: 'ubuntu-22.04'
 
   steps:
+    - checkout: self
+      submodules: true
+
     - script: |
         set -ex
         mkdir -p $(DEV)

.azure/azure-pipelines-mac.yml

@@ -81,6 +81,8 @@ jobs:
 #        brew update || brew update
 #        brew upgrade $PACKAGES
   steps:
+    - checkout: self
+      submodules: true
     - script: |
         set -ex
         PACKAGES="glib gobject-introspection libsndfile pkg-config jack dbus-glib pulseaudio portaudio sdl2 libomp readline"
@@ -163,6 +165,8 @@ jobs:
   pool:
     vmImage: $(imageName)
   steps:
+    - checkout: self
+      submodules: true
     - script: |
         set -ex
         brew install wget pkg-config

.azure/azure-pipelines-win.yml

@@ -64,6 +64,8 @@ jobs:
   pool:
     vmImage: 'windows-2022'
   steps:
+    - checkout: self
+      submodules: true
     - task: DownloadBuildArtifacts@0
       inputs:
         buildType: specific
@@ -184,6 +186,8 @@ jobs:
   pool:
     vmImage: 'windows-2022'
   steps:
+    - checkout: self
+      submodules: true
     - script: |
         @ECHO ON
         mkdir d:\deps || exit -1
@@ -245,6 +249,8 @@ jobs:
   pool:
     vmImage: 'windows-2022'
   steps:
+    - checkout: self
+      submodules: true
     - task: DownloadBuildArtifacts@0
       inputs:
         buildType: specific

.github/workflows/codeql-analysis.yml

@@ -40,6 +40,8 @@ jobs:
     steps:
     - name: Checkout repository
       uses: actions/checkout@v4
+      with:
+        submodules: recursive
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL

.github/workflows/linux.yml

@@ -45,6 +45,8 @@ jobs:
 
     steps:
     - uses: actions/checkout@v4
+      with:
+        submodules: recursive
 
     - name: Add apt-get repositories
       run: sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test

.github/workflows/sonarcloud.yml

@@ -28,6 +28,8 @@ jobs:
       with:
         # Disabling shallow clone is recommended for improving relevancy of reporting
         fetch-depth: 0
+        submodules: recursive
+
 
     - name: Add apt-get repositories
       run: |

.github/workflows/windows.yml

@@ -37,6 +37,8 @@ jobs:
 
     steps:
     - uses: actions/checkout@v4
+      with:
+        submodules: recursive
 
     - name: '${{ matrix.icon }} Setup MSYS2'
       uses: msys2/setup-msys2@v2

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "test/manual"]
 	path = test/manual
 	url = https://github.com/FluidSynth/testdata.git
+[submodule "gcem"]
+	path = gcem
+	url = https://github.com/kthohr/gcem.git

CMakeLists.txt

@@ -125,7 +125,7 @@ endif ( CMAKE_SYSTEM MATCHES "OS2" )
 set(CMAKE_C_STANDARD 90)
 
 # the default C++ standard to use for all targets
-set(CMAKE_CXX_STANDARD 98)
+set(CMAKE_CXX_STANDARD 11)
 
 # whether to use gnu extensions
 set(CMAKE_C_EXTENSIONS ON)

src/CMakeLists.txt

@@ -108,6 +108,15 @@ endif ( OBOE_SUPPORT )
 set ( config_SOURCES ${FluidSynth_BINARY_DIR}/config.h )
 
 set ( libfluidsynth_SOURCES
+    gentables/fluid_ct2hz.cpp
+    gentables/fluid_cb2amp.cpp
+    gentables/fluid_concave.cpp
+    gentables/fluid_convex.cpp
+    gentables/fluid_pan.cpp
+    gentables/fluid_interp_coeff.cpp
+    gentables/fluid_interp_coeff_linear.cpp
+    gentables/fluid_interp_coeff_sinc7.cpp
+    gentables/ConstExprArr.hpp
     utils/fluid_conv.c
     utils/fluid_conv.h
     utils/fluid_hash.c
@@ -281,6 +290,7 @@ target_include_directories ( libfluidsynth-OBJ PRIVATE
     ${FluidSynth_SOURCE_DIR}/src/sfloader
     ${FluidSynth_SOURCE_DIR}/src/bindings
     ${FluidSynth_SOURCE_DIR}/include
+    ${FluidSynth_SOURCE_DIR}/gcem/include
 )
 
 if ( LIBFLUID_CPPFLAGS )
@@ -576,27 +586,3 @@ install(EXPORT FluidSynthTargets
         NAMESPACE FluidSynth::
         DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/fluidsynth
 )
-
-# ******* Auto Generated Lookup Tables ******
-
-include(ExternalProject)
-
-set (GENTAB_SDIR ${CMAKE_CURRENT_SOURCE_DIR}/gentables)
-set (GENTAB_BDIR ${CMAKE_CURRENT_BINARY_DIR}/gentables)
-
-# Use external project to ensure that cmake uses the host compiler when building make_tables.exe
-# To fix cross-compiling fluidsynth from Win32 to ARM (using vcpkg), we need to pass the current generator
-# on to the external project, otherwise (for some unknown reason) the target compiler will be used rather
-# than the host compiler.
-
-ExternalProject_Add(gentables
-    DOWNLOAD_COMMAND ""
-    SOURCE_DIR ${GENTAB_SDIR}
-    BINARY_DIR ${GENTAB_BDIR}
-    CONFIGURE_COMMAND
-        "${CMAKE_COMMAND}" -DCMAKE_VERBOSE_MAKEFILE=${CMAKE_VERBOSE_MAKEFILE} -G "${CMAKE_GENERATOR}" -B "${GENTAB_BDIR}" "${GENTAB_SDIR}"
-    BUILD_COMMAND
-        "${CMAKE_COMMAND}" --build "${GENTAB_BDIR}"
-    INSTALL_COMMAND ${GENTAB_BDIR}/make_tables.exe "${FluidSynth_BINARY_DIR}/"
-)
-add_dependencies(libfluidsynth-OBJ gentables)

src/gentables/ConstExprArr.hpp

@@ -0,0 +1,59 @@
+
+#pragma once
+
+#include "fluidsynth_priv.h"
+
+
+struct IsBoundary
+{
+    // Checks whether N is a multiple of 10
+    static constexpr bool chunk10(int N)
+    {
+        return (N >= 0) && (N % 10 == 0);
+    }
+};
+
+// === Recursive Template Struct: ConstExprArr_impl ===
+// This struct recursively instantiates itself, decrementing N and accumulating template parameters
+// in Rest... Each instantiation pushes N onto the Rest... pack, so eventually the values are
+// collected as 1, 2, ..., N-1, N in Rest..., until we reach N = 0.
+template<typename F, bool NisMult10, int N, int... Rest> struct ConstExprArr_impl
+{
+    static constexpr auto &value = ConstExprArr_impl<F, IsBoundary::chunk10(N - 1), N - 1, N, Rest...>::value;
+};
+
+// === Partial Specialization for N==0 ===
+// When N == 0, this specialization is used.
+// It defines a static constant array value containing the values as calculated by the functor.
+// At this point, Rest... actually contains all previous N values, so the array will be { 0, 1, 2, ..., N }
+template<typename F, int... Rest> struct ConstExprArr_impl<F, true, 0, Rest...>
+{
+    static constexpr fluid_real_t value[] = { F::calc(0), F::calc(Rest)... };
+};
+
+// === Partial Specialization whenever N is positive and a multiple of 10 ===
+// The sole purpose of this specialization is to allow compilation with MSVC. MSVC has a hard-coded
+// recursive template instantiation limit of 500. By chunking the recursion in steps of 10 whenever
+// N is a multiple of 10, we drastically reduce the template recursion depth, allowing the code to
+// compile for MSVC.
+template<typename F, int N, int... Rest> struct ConstExprArr_impl<F, true, N, Rest...>
+{
+    static constexpr auto &value =
+    ConstExprArr_impl<F, IsBoundary::chunk10(N - 10), N - 10, N - 9, N - 8, N - 7, N - 6, N - 5, N - 4, N - 3, N - 2, N - 1, N, Rest...>::value;
+};
+
+// Out-of-class Definition of the Static Array (needed for linkage)
+template<typename F, int... Rest> constexpr fluid_real_t ConstExprArr_impl<F, true, 0, Rest...>::value[];
+
+template<typename F, int N> struct ConstExprArr
+{
+    static_assert(N > 0, "N must be greater 0");
+
+    // invokes the Recursive Template Struct
+    // N-1 because we want to exclude the last element, i.e. only from 0 to N-1
+    static constexpr auto &value = ConstExprArr_impl<F, IsBoundary::chunk10(N - 1), N - 1>::value;
+
+    ConstExprArr() = delete;
+    ConstExprArr(const ConstExprArr &) = delete;
+    ConstExprArr(ConstExprArr &&) = delete;
+};

src/gentables/fluid_cb2amp.cpp

@@ -0,0 +1,22 @@
+
+#include "utils/fluid_conv_tables.h"
+#include "gentables/ConstExprArr.hpp"
+
+#include "gcem.hpp"
+
+struct Cb2AmpFunctor
+{
+    static constexpr fluid_real_t calc(int i)
+    {
+        /* centibels to amplitude conversion
+         * Note: SF2.01 section 8.1.3: Initial attenuation range is
+         * between 0 and 144 dB. Therefore a negative attenuation is
+         * not allowed.
+         */
+       return gcem::pow(10.0L, static_cast<fluid_real_t>(i) / -200.0L);
+    }
+};
+
+extern "C" const constexpr auto fluid_cb2amp_tab_cpp = ConstExprArr<Cb2AmpFunctor, FLUID_CB_AMP_SIZE>::value;
+
+extern "C" const fluid_real_t *const fluid_cb2amp_tab = fluid_cb2amp_tab_cpp;

src/gentables/fluid_concave.cpp

@@ -0,0 +1,24 @@
+
+#include "utils/fluid_conv_tables.h"
+#include "gentables/ConstExprArr.hpp"
+
+#include "gcem.hpp"
+
+struct ConcaveFunctor
+{
+    /* There seems to be an error in the specs. The equations are
+       implemented according to the pictures on SF2.01 page 73. */
+    static constexpr fluid_real_t calc(int i)
+    {
+        return ((i == 0)
+            ? 0
+            : ((i == FLUID_VEL_CB_SIZE - 1)
+                ? 1
+                : ((-200.0L * 2 / FLUID_PEAK_ATTENUATION) * gcem::log(((FLUID_VEL_CB_SIZE - 1) - i) / (FLUID_VEL_CB_SIZE - 1.0L)) / GCEM_LOG_10)
+                ));
+    }
+};
+
+extern "C" const constexpr auto fluid_concave_tab_cpp = ConstExprArr<ConcaveFunctor, FLUID_VEL_CB_SIZE>::value;
+
+extern "C" const fluid_real_t *const fluid_concave_tab = fluid_concave_tab_cpp;

src/gentables/fluid_convex.cpp

@@ -0,0 +1,24 @@
+
+#include "utils/fluid_conv_tables.h"
+#include "gentables/ConstExprArr.hpp"
+
+#include "gcem.hpp"
+
+struct ConvexFunctor
+{
+    /* There seems to be an error in the specs. The equations are
+       implemented according to the pictures on SF2.01 page 73. */
+    static constexpr fluid_real_t calc(int i)
+    {
+        return ((i == 0)
+            ? 0
+            : ((i == FLUID_VEL_CB_SIZE - 1)
+                ? 1
+                : (1.0L - ((-200.0L * 2 / FLUID_PEAK_ATTENUATION) * gcem::log(i / (FLUID_VEL_CB_SIZE - 1.0L)) / GCEM_LOG_10))
+                ));
+    }
+};
+
+extern "C" const constexpr auto fluid_convex_tab_cpp = ConstExprArr<ConvexFunctor, FLUID_VEL_CB_SIZE>::value;
+
+extern "C" const fluid_real_t *const fluid_convex_tab = fluid_convex_tab_cpp;

src/gentables/fluid_ct2hz.cpp

@@ -0,0 +1,20 @@
+
+#include "utils/fluid_conv_tables.h"
+#include "gentables/ConstExprArr.hpp"
+
+#include "gcem.hpp"
+
+struct Ct2HzFunctor
+{
+    static constexpr fluid_real_t calc(int i)
+    {
+        // 6,875 is just a factor that we already multiply into the lookup table to save
+        // that multiplication in fluid_ct2hz_real()
+        // 6.875 Hz because 440Hz / 2^6
+        return 6.875 * gcem::pow(2.0, static_cast<fluid_real_t>(i) / 1200.0);
+    }
+};
+
+extern "C" const constexpr auto fluid_ct2hz_tab_cpp = ConstExprArr<Ct2HzFunctor, FLUID_CENTS_HZ_SIZE>::value;
+
+extern "C" const fluid_real_t *const fluid_ct2hz_tab = fluid_ct2hz_tab_cpp;