From 4f7a6256a9fbbc17aadc5b28c3a30961f6a42b77 Mon Sep 17 00:00:00 2001
From: David Williams <david@volumesoffun.com>
Date: Sat, 29 Dec 2012 00:11:23 +0000
Subject: [PATCH] The throwing of exceptions can now be disabled, and in this
 case a handler function is called instead.

---
 library/PolyVoxCore/CMakeLists.txt            |  1 +
 .../include/PolyVoxCore/Impl/ErrorHandling.h  | 25 ++++++++++++++++++-
 library/PolyVoxCore/source/Impl/Utility.cpp   | 12 ++++-----
 3 files changed, 30 insertions(+), 8 deletions(-)

diff --git a/library/PolyVoxCore/CMakeLists.txt b/library/PolyVoxCore/CMakeLists.txt
index 34deabef..f964a8d5 100644
--- a/library/PolyVoxCore/CMakeLists.txt
+++ b/library/PolyVoxCore/CMakeLists.txt
@@ -94,6 +94,7 @@ SET(CORE_INC_FILES
 )
 
 SET(IMPL_SRC_FILES
+	source/Impl/ErrorHandling.cpp
 	source/Impl/MarchingCubesTables.cpp
 	source/Impl/RandomUnitVectors.cpp
 	source/Impl/RandomVectors.cpp
diff --git a/library/PolyVoxCore/include/PolyVoxCore/Impl/ErrorHandling.h b/library/PolyVoxCore/include/PolyVoxCore/Impl/ErrorHandling.h
index 88415f74..d3ef8b49 100644
--- a/library/PolyVoxCore/include/PolyVoxCore/Impl/ErrorHandling.h
+++ b/library/PolyVoxCore/include/PolyVoxCore/Impl/ErrorHandling.h
@@ -26,8 +26,10 @@ freely, subject to the following restrictions:
 
 #include <cstdlib>  //For std::exit
 #include <iostream> //For std::cerr
+#include <stdexcept>
 
 #define POLYVOX_ASSERTS_ENABLED
+//#define POLYVOX_THROW_ENABLED
 
 #if defined(_MSC_VER)
     #define POLYVOX_HALT() __debugbreak()
@@ -54,7 +56,7 @@ freely, subject to the following restrictions:
 			{ \
 				std::cerr << std::endl << std::endl; \
 				std::cerr << "    PolyVox Assertion Failed!" << std::endl; \
-				std::cerr << "    -------------------------" << std::endl; \
+				std::cerr << "    =========================" << std::endl; \
 				std::cerr << "    Condition: " << #condition << std::endl; \
 				std::cerr << "    Message:   " << (message) << std::endl; \
 				std::cerr << "    Location:  " << "Line " << __LINE__ << " of " << __FILE__ << std::endl << std::endl; \
@@ -98,4 +100,25 @@ freely, subject to the following restrictions:
 	#define POLYVOX_STATIC_ASSERT(condition, message) StaticAssert<(condition)>::ERROR_The_static_assertion_has_failed();
 #endif
 
+/*
+ * Exceptions
+ * ----------
+ * ...
+ */
+#ifdef POLYVOX_THROW_ENABLED
+	#define POLYVOX_THROW(type, message) throw type((message))
+#else
+	namespace PolyVox
+	{
+		typedef void (*ThrowHandler)(std::exception& e, const char* file, int line);
+
+		ThrowHandler getThrowHandler();
+		void setThrowHandler(ThrowHandler newHandler);
+	}
+
+	#define POLYVOX_THROW(type, message) \
+		type except = (type)((message)); \
+		getThrowHandler()((except), __FILE__, __LINE__)
+#endif
+
 #endif //__PolyVox_ErrorHandling_H__
diff --git a/library/PolyVoxCore/source/Impl/Utility.cpp b/library/PolyVoxCore/source/Impl/Utility.cpp
index 6e907ab9..c82c9630 100644
--- a/library/PolyVoxCore/source/Impl/Utility.cpp
+++ b/library/PolyVoxCore/source/Impl/Utility.cpp
@@ -21,11 +21,9 @@ freely, subject to the following restrictions:
     distribution. 	
 *******************************************************************************/
 
+#include "PolyVoxCore/Impl/ErrorHandling.h"
 #include "PolyVoxCore/Impl/Utility.h"
 
-#include <cassert>
-#include <stdexcept>
-
 namespace PolyVox
 {
 	//Note: this function only works for inputs which are a power of two and not zero
@@ -33,17 +31,17 @@ namespace PolyVox
 	uint8_t logBase2(uint32_t uInput)
 	{
 		//Debug mode validation
-		assert(uInput != 0);
-		assert(isPowerOf2(uInput));
+		POLYVOX_ASSERT(uInput != 0, "Cannot compute the log of zero.");
+		POLYVOX_ASSERT(isPowerOf2(uInput), "Input must be a power of two in order to compute the log.");
 
 		//Release mode validation
 		if(uInput == 0)
 		{
-			throw std::invalid_argument("Cannot compute the log of zero.");
+			POLYVOX_THROW(std::invalid_argument, "Cannot compute the log of zero.");
 		}
 		if(!isPowerOf2(uInput))
 		{
-			throw std::invalid_argument("Input must be a power of two in order to compute the log.");
+			POLYVOX_THROW(std::invalid_argument, "Input must be a power of two in order to compute the log.");
 		}
 
 		uint32_t uResult = 0;