use cmake variable

Author: neka-nat

src/cupoch/visualization/CMakeLists.txt

@@ -2,15 +2,15 @@ file(GLOB SHADER_FILES "shader/glsl/*.glsl")
 
 add_custom_command(
     OUTPUT ${PROJECT_SOURCE_DIR}/src/cupoch/visualization/shader/shader.h
-    COMMAND python3 ${PROJECT_SOURCE_DIR}/scripts/encode_shader.py shader.h
+    COMMAND ${PYTHON_EXECUTABLE} ${PROJECT_SOURCE_DIR}/scripts/encode_shader.py shader.h
     WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}/src/cupoch/visualization/shader/
     DEPENDS ${SHADER_FILES}
 )
 
 foreach(file ${SHADER_FILES})
     add_custom_command(
         OUTPUT ${PROJECT_SOURCE_DIR}/src/cupoch/visualization/shader/shader.h
-        COMMAND python3 ${PROJECT_SOURCE_DIR}/scripts/encode_shader.py shader.h ${file}
+        COMMAND ${PYTHON_EXECUTABLE} ${PROJECT_SOURCE_DIR}/scripts/encode_shader.py shader.h ${file}
         WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}/src/cupoch/visualization/shader/
         DEPENDS ${SHADER_FILES}
         APPEND