diff --git a/togl/linuxwin/cglmtex.cpp b/togl/linuxwin/cglmtex.cpp
index a9b174fe..54ceb48e 100644
--- a/togl/linuxwin/cglmtex.cpp
+++ b/togl/linuxwin/cglmtex.cpp
@@ -1670,7 +1670,7 @@ void CGLMTex::Lock( GLMTexLockParams *params, char** addressOut, int* yStrideOut
 	{
 		*addressOut = (char*)ReadTexels( desc, true, params->m_readonly );
 
-		if( !params->m_readonly )
+		if( params->m_readonly == false )
 			m_mapped = (GLubyte*)*addressOut;
 	}
 	else
@@ -1763,7 +1763,7 @@ void CGLMTex::Unlock( GLMTexLockParams *params )
 				
 				// fullyDirty |= (m_sliceFlags[ desc->m_sliceIndex ] & kSliceStorageValid);
 				
-				if( m_layout->m_key.m_texFlags & kGLMTexDynamic )
+				if( m_layout->m_key.m_texFlags & kGLMTexDynamic && m_mapped )
 				{
 					gGL->glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER);
 
diff --git a/togl/linuxwin/dxabstract.cpp b/togl/linuxwin/dxabstract.cpp
index bb62845f..b01541dd 100644
--- a/togl/linuxwin/dxabstract.cpp
+++ b/togl/linuxwin/dxabstract.cpp
@@ -1041,7 +1041,7 @@ HRESULT IDirect3DSurface9::LockRect(D3DLOCKED_RECT* pLockedRect,CONST RECT* pRec
 		lockreq.m_readback = true;
 	}
 
-	lockreq.m_readonly = Flags & D3DLOCK_READONLY;
+	lockreq.m_readonly = (Flags & D3DLOCK_READONLY) ? true : false;
 
 	char	*lockAddress;
 	int		yStride;
diff --git a/togles/linuxwin/cglmtex.cpp b/togles/linuxwin/cglmtex.cpp
index 6c9bd136..a5811f3b 100644
--- a/togles/linuxwin/cglmtex.cpp
+++ b/togles/linuxwin/cglmtex.cpp
@@ -3946,7 +3946,7 @@ void CGLMTex::Lock( GLMTexLockParams *params, char** addressOut, int* yStrideOut
 		// (odds are we'll never request anything but a whole slice to be read..)
 		*addressOut = (char*)ReadTexels( desc, true, params->m_readonly );
 
-		if( !params->m_readonly )
+		if( params->m_readonly == false )
 			m_mapped = (GLubyte*)*addressOut;
 	}
 	else
@@ -4039,7 +4039,7 @@ void CGLMTex::Unlock( GLMTexLockParams *params )
 				
 				// fullyDirty |= (m_sliceFlags[ desc->m_sliceIndex ] & kSliceStorageValid);
 				
-				if( m_layout->m_key.m_texFlags & kGLMTexDynamic )
+				if( m_layout->m_key.m_texFlags & kGLMTexDynamic && m_mapped )
 				{
 					gGL->glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER);
 
diff --git a/togles/linuxwin/dxabstract.cpp b/togles/linuxwin/dxabstract.cpp
index 4496fc4d..67d391e7 100644
--- a/togles/linuxwin/dxabstract.cpp
+++ b/togles/linuxwin/dxabstract.cpp
@@ -1041,7 +1041,7 @@ HRESULT IDirect3DSurface9::LockRect(D3DLOCKED_RECT* pLockedRect,CONST RECT* pRec
 		lockreq.m_readback = true;
 	}
 
-	lockreq.m_readonly = Flags & D3DLOCK_READONLY;
+	lockreq.m_readonly = (Flags & D3DLOCK_READONLY) ? true : false;
 
 	char	*lockAddress;
 	int		yStride;