Improved shader conversion custom CMake commands to properly detect changes and not run every build

3 files changed, 45 insertions, 68 deletions

diff --git a/Graphics/GraphicsEngineD3DBase/CMakeLists.txt b/Graphics/GraphicsEngineD3DBase/CMakeLists.txt
index 0f208b6d..f0b306b5 100644
--- a/Graphics/GraphicsEngineD3DBase/CMakeLists.txt
+++ b/Graphics/GraphicsEngineD3DBase/CMakeLists.txt
@@ -27,33 +27,29 @@ set(SOURCE
     src/ShaderResources.cpp
 )
 
-add_library(Diligent-GraphicsEngineD3DBase STATIC 
-    ${SOURCE} ${INCLUDE} ${INTERFACE} include/HLSLDefinitions_inc.fxh
-)
+set(HLSL_DEFINITIONS include/HLSLDefinitions.fxh)
 
-set_source_files_properties(
-    ${CMAKE_CURRENT_SOURCE_DIR}/include/HLSLDefinitions_inc.fxh
-    PROPERTIES GENERATED TRUE
-)
+# We must use the full path, otherwise the build system will not be able to properly detect
+# changes and shader conversion custom command will run every time
+set(HLSL_DEFINITIONS_INC ${CMAKE_CURRENT_SOURCE_DIR}/include/HLSLDefinitions_inc.fxh)
+set_source_files_properties(${HLSL_DEFINITIONS_INC} PROPERTIES GENERATED TRUE)
 
-# Create custom target to convert HLSLDefinitions.fxh to HLSLDefinitions_inc.fxh
-add_custom_target(Diligent-ProcessHLSLDefinitions
-SOURCES
-    include/HLSLDefinitions.fxh
+add_library(Diligent-GraphicsEngineD3DBase STATIC 
+    ${SOURCE} ${INCLUDE} ${INTERFACE}
+
+    # A target created in the same directory (CMakeLists.txt file) that specifies any output of the 
+    # custom command as a source file is given a rule to generate the file using the command at build time. 
+    ${HLSL_DEFINITIONS_INC}
 )
 
-add_custom_command(TARGET Diligent-ProcessHLSLDefinitions 
-                   # Unfortunately it is not possible to set TARGET directly to Diligent-GraphicsEngineD3DBase
-                   # because PRE_BUILD is only supported on Visual Studio 8 or later. For all other generators 
-                   # PRE_BUILD is treated as PRE_LINK.
-                   COMMAND ${FILE2STRING_PATH} include/HLSLDefinitions.fxh include/HLSLDefinitions_inc.fxh
+add_custom_command(OUTPUT ${HLSL_DEFINITIONS_INC} # We must use full path here!
+                   COMMAND ${FILE2STRING_PATH} ${HLSL_DEFINITIONS} include/HLSLDefinitions_inc.fxh
                    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+                   MAIN_DEPENDENCY ${HLSL_DEFINITIONS}
                    COMMENT "Processing HLSLDefinitions.fxh"
                    VERBATIM
 )
 
-add_dependencies(Diligent-GraphicsEngineD3DBase Diligent-ProcessHLSLDefinitions)
-
 add_library(Diligent-GraphicsEngineD3DBaseInterface INTERFACE)
 target_link_libraries(Diligent-GraphicsEngineD3DBaseInterface INTERFACE Diligent-GraphicsEngineInterface)
 target_include_directories(Diligent-GraphicsEngineD3DBaseInterface INTERFACE interface)
@@ -63,7 +59,7 @@ PUBLIC
     include
 )
 
-target_link_libraries(Diligent-GraphicsEngineD3DBase 
+target_link_libraries(Diligent-GraphicsEngineD3DBase
 PUBLIC
     Diligent-BuildSettings 
     Diligent-GraphicsEngine 
@@ -80,9 +76,6 @@ source_group("generated" FILES include/HLSLDefinitions_inc.fxh)
 set_target_properties(Diligent-GraphicsEngineD3DBase PROPERTIES
     FOLDER DiligentCore/Graphics
 )
-set_target_properties(Diligent-ProcessHLSLDefinitions PROPERTIES
-    FOLDER DiligentCore/Graphics/Helper
-)
 
 if(DILIGENT_INSTALL_CORE)
     install_core_lib(Diligent-GraphicsEngineD3DBase)
diff --git a/Graphics/GraphicsEngineVulkan/CMakeLists.txt b/Graphics/GraphicsEngineVulkan/CMakeLists.txt
index 5e0a3558..a8669ae5 100644
--- a/Graphics/GraphicsEngineVulkan/CMakeLists.txt
+++ b/Graphics/GraphicsEngineVulkan/CMakeLists.txt
@@ -110,31 +110,21 @@ set(VULKAN_UTILS_SRC
     src/VulkanUtilities/VulkanPhysicalDevice.cpp
 )
 
-set(GENERATE_MIPS_SHADER
-    shaders/GenerateMipsCS.csh
-)
-set(GENERATE_MIPS_SHADER_INC
-    shaders/GenerateMipsCS_inc.h
-)
+set(GENERATE_MIPS_SHADER shaders/GenerateMipsCS.csh)
 
+# We must use the full path, otherwise the build system will not be able to properly detect
+# changes and shader conversion custom command will run every time
+set(GENERATE_MIPS_SHADER_INC ${CMAKE_CURRENT_SOURCE_DIR}/shaders/GenerateMipsCS_inc.h)
 set_source_files_properties(
-    ${CMAKE_CURRENT_SOURCE_DIR}/${GENERATE_MIPS_SHADER_INC}
+    ${GENERATE_MIPS_SHADER_INC}
     PROPERTIES GENERATED TRUE
 )
 
-# Create custom target to convert GenerateMipsCS.csh to GenerateMipsCS_inc.h
-add_custom_target(Diligent-ProcessGenerateMipsVkShader
-SOURCES
-    ${GENERATE_MIPS_SHADER}
-)
-
-add_custom_command(TARGET Diligent-ProcessGenerateMipsVkShader 
-                   # Unfortunately it is not possible to set TARGET directly to Diligent-GraphicsEngineVk-*
-                   # because PRE_BUILD is only supported on Visual Studio 8 or later. For all other generators 
-                   # PRE_BUILD is treated as PRE_LINK.
-                   COMMAND ${FILE2STRING_PATH} ${GENERATE_MIPS_SHADER} ${GENERATE_MIPS_SHADER_INC}
+add_custom_command(OUTPUT ${GENERATE_MIPS_SHADER_INC} # We must use full path here!
+                   COMMAND ${FILE2STRING_PATH} ${GENERATE_MIPS_SHADER} shaders/GenerateMipsCS_inc.h
                    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
                    COMMENT "Processing GenerateMipsCS.csh"
+                   MAIN_DEPENDENCY ${GENERATE_MIPS_SHADER}
                    VERBATIM
 )
 
@@ -150,7 +140,12 @@ INTERFACE
 )
 
 add_library(Diligent-GraphicsEngineVk-static STATIC 
-    ${SRC} ${VULKAN_UTILS_SRC} ${INTERFACE} ${INCLUDE} ${VULKAN_UTILS_INCLUDE} ${GENERATE_MIPS_SHADER} ${GENERATE_MIPS_SHADER_INC}
+    ${SRC} ${VULKAN_UTILS_SRC} ${INTERFACE} ${INCLUDE} ${VULKAN_UTILS_INCLUDE} ${GENERATE_MIPS_SHADER}
+    
+    # A target created in the same directory (CMakeLists.txt file) that specifies any output of the 
+    # custom command as a source file is given a rule to generate the file using the command at build time. 
+    ${GENERATE_MIPS_SHADER_INC}
+
     readme.md
 )
 
@@ -165,8 +160,6 @@ if(MSVC)
     )
 endif()
 
-add_dependencies(Diligent-GraphicsEngineVk-static Diligent-ProcessGenerateMipsVkShader)
-
 target_include_directories(Diligent-GraphicsEngineVk-static 
 PRIVATE
     include
@@ -300,10 +293,6 @@ set_source_files_properties(
     readme.md PROPERTIES HEADER_FILE_ONLY TRUE
 )
 
-set_target_properties(Diligent-ProcessGenerateMipsVkShader PROPERTIES
-    FOLDER DiligentCore/Graphics/Helper
-)
-
 if(DILIGENT_INSTALL_CORE)
     install_core_lib(Diligent-GraphicsEngineVk-shared)
     install_core_lib(Diligent-GraphicsEngineVk-static)
diff --git a/Graphics/HLSL2GLSLConverterLib/CMakeLists.txt b/Graphics/HLSL2GLSLConverterLib/CMakeLists.txt
index 109687df..839d9c20 100644
--- a/Graphics/HLSL2GLSLConverterLib/CMakeLists.txt
+++ b/Graphics/HLSL2GLSLConverterLib/CMakeLists.txt
@@ -18,13 +18,21 @@ set(SOURCE
     src/HLSL2GLSLConverterObject.cpp
 )
 
-add_library(Diligent-HLSL2GLSLConverterLib STATIC ${SOURCE} ${INTERFACE} ${INCLUDE} include/GLSLDefinitions_inc.h)
-set_common_target_properties(Diligent-HLSL2GLSLConverterLib)
+set(GLSL_DEFINITIONS include/GLSLDefinitions.h)
+
+# We must use the full path, otherwise the build system will not be able to properly detect
+# changes and shader conversion custom command will run every time
+set(GLSL_DEFINITIONS_INC ${CMAKE_CURRENT_SOURCE_DIR}/include/GLSLDefinitions_inc.h)
+set_source_files_properties(${GLSL_DEFINITIONS_INC} PROPERTIES GENERATED TRUE)
 
-set_source_files_properties(
-    ${CMAKE_CURRENT_SOURCE_DIR}/include/GLSLDefinitions_inc.h
-    PROPERTIES GENERATED TRUE
+add_library(Diligent-HLSL2GLSLConverterLib STATIC
+    ${SOURCE} ${INTERFACE} ${INCLUDE}
+
+    # A target created in the same directory (CMakeLists.txt file) that specifies any output of the 
+    # custom command as a source file is given a rule to generate the file using the command at build time. 
+    ${GLSL_DEFINITIONS_INC}
 )
+set_common_target_properties(Diligent-HLSL2GLSLConverterLib)
 
 target_include_directories(Diligent-HLSL2GLSLConverterLib 
 PUBLIC 
@@ -44,26 +52,13 @@ PUBLIC
 )
 
 if(NOT FILE2STRING_PATH STREQUAL "")
-    # Create custom target to convert GLSLDefinitions.h to GLSLDefinitions_inc.h
-    add_custom_target(Diligent-ProcessGLSLDefinitions 
-    SOURCES
-        include/GLSLDefinitions.h
-    )
-
-    add_custom_command(TARGET Diligent-ProcessGLSLDefinitions 
-                       # Unfortunately it is not possible to set TARGET directly to HLSL2GLSLConverterLib
-                       # because PRE_BUILD is only supported on Visual Studio 8 or later. For all other generators 
-                       # PRE_BUILD is treated as PRE_LINK.
-                       COMMAND ${FILE2STRING_PATH} include/GLSLDefinitions.h include/GLSLDefinitions_inc.h
+    add_custom_command(OUTPUT ${GLSL_DEFINITIONS_INC} # We must use full path here!
+                       COMMAND ${FILE2STRING_PATH} ${GLSL_DEFINITIONS} include/GLSLDefinitions_inc.h
                        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+                       MAIN_DEPENDENCY ${GLSL_DEFINITIONS}
                        COMMENT "Processing GLSLDefinitions.h"
                        VERBATIM
     )
-
-    add_dependencies(Diligent-HLSL2GLSLConverterLib Diligent-ProcessGLSLDefinitions)
-    set_target_properties(Diligent-ProcessGLSLDefinitions PROPERTIES
-        FOLDER DiligentCore/Graphics/Helper
-    )
 else()
     message(WARNING "File2String utility is currently unavailable on this host system. This is not an issues unless you modify GLSLDefinitions.h file")
 endif()