love.graphics.newGeometry now takes an optional draw mode argument ("fan", "strip", or "triangles".) "fan" is the default.

This allows for more diverse and complex Geometries, provided the lover understands how to use each mode. See http://escience.anu.edu.au/lecture/cg/surfaceModeling/image/surfaceModeling015.png

Changed love.graphics.newGeometry to optionally accept vertices as individual arguments instead of just a table of vertices (resolves issue #651).
Changed Geometry:setVertex to optionally accept a table containing x,y,u,v,r,g,b,a instead of just individual arguments.

Added Geometry:set/getDrawMode.

Removed the convex-check in love.graphics.newGeometry (all geometry modes have at least some form of concavity support, lovers can do their own check if needed with love.math.isConvex.)

Added an optional "vertex map" table argument to love.graphics.newGeometry (AKA a vertex index array / element array in graphics programming lingo.)
This allows lovers to change the order in which the vertices are used when drawing, or re-use a single vertex multiple times for different parts of the Geometry.
This is especially useful in the "triangles" Geometry draw mode. The vertex map lets you draw very complex (and concave) shapes / meshes without duplicating vertex data.

Added Geometry:set/getVertexMap.

src/modules/graphics/opengl/wrap_Geometry.cpp

@@ -34,7 +34,6 @@ Geometry *luax_checkgeometry(lua_State *L, int idx)
 	return luax_checktype<Geometry>(L, idx, "Geometry", GRAPHICS_GEOMETRY_T);
 }
 
-// different name than in Geometry.cpp to make the triangulation transparent
 int w_Geometry_getVertexCount(lua_State *L)
 {
 	Geometry *geom = luax_checkgeometry(L, 1);
@@ -69,17 +68,37 @@ int w_Geometry_getVertex(lua_State *L)
 int w_Geometry_setVertex(lua_State *L)
 {
 	Geometry *geom = luax_checkgeometry(L, 1);
-	size_t i = size_t(luaL_checkint(L, 2));
+	size_t i = size_t(luaL_checkinteger(L, 2));
 
 	vertex v;
-	v.x = luaL_checknumber(L, 3);
-	v.y = luaL_checknumber(L, 4);
-	v.s = luaL_checknumber(L, 5);
-	v.t = luaL_checknumber(L, 6);
-	v.r = luaL_optint(L,  7, 255);
-	v.g = luaL_optint(L,  8, 255);
-	v.b = luaL_optint(L,  9, 255);
-	v.a = luaL_optint(L, 10, 255);
+
+	if (lua_istable(L, 3))
+	{
+		for (int i = 1; i <= 8; i++)
+			lua_rawgeti(L, 3, i);
+
+		v.x = luaL_checknumber(L, -8);
+		v.y = luaL_checknumber(L, -7);
+		v.s = luaL_checknumber(L, -6);
+		v.t = luaL_checknumber(L, -5);
+		v.r = luaL_optinteger(L, -4, 255);
+		v.g = luaL_optinteger(L, -3, 255);
+		v.b = luaL_optinteger(L, -2, 255);
+		v.a = luaL_optinteger(L, -1, 255);
+
+		lua_pop(L, 8);
+	}
+	else
+	{
+		v.x = luaL_checknumber(L, 3);
+		v.y = luaL_checknumber(L, 4);
+		v.s = luaL_checknumber(L, 5);
+		v.t = luaL_checknumber(L, 6);
+		v.r = luaL_optinteger(L,  7, 255);
+		v.g = luaL_optinteger(L,  8, 255);
+		v.b = luaL_optinteger(L,  9, 255);
+		v.a = luaL_optinteger(L, 10, 255);
+	}
 
 	try
 	{
@@ -117,6 +136,82 @@ int w_Geometry_hasVertexColors(lua_State *L)
 	return 1;
 }
 
+int w_Geometry_getDrawMode(lua_State *L)
+{
+	Geometry *geom = luax_checkgeometry(L, 1);
+
+	Geometry::DrawMode mode = geom->getDrawMode();
+	const char *str;
+
+	if (!Geometry::getConstant(mode, str))
+		return luaL_error(L, "Unknown Geometry draw mode");
+
+	lua_pushstring(L, str);
+
+	return 1;
+}
+
+int w_Geometry_getVertexMap(lua_State *L)
+{
+	Geometry *g = luax_checkgeometry(L, 1);
+
+	size_t elementcount = g->getElementCount();
+	const uint16 *elements = g->getElementArray();
+
+	if (elementcount == 0 || elements == 0)
+		return 0;
+
+	lua_createtable(L, elementcount, 0);
+	for (size_t i = 0; i < elementcount; i++)
+	{
+		lua_pushinteger(L, elements[i]);
+		lua_rawseti(L, -2, i + 1);
+	}
+
+	return 1;
+}
+
+int w_Geometry_setVertexMap(lua_State *L)
+{
+	Geometry *g = luax_checkgeometry(L, 1);
+
+	for (int i = lua_gettop(L); i >= 2; i--)
+	{
+		if (lua_isnil(L, i))
+			lua_pop(L, 1);
+		else
+			break;
+	}
+
+	bool is_table = lua_istable(L, 2);
+	int nargs = is_table ? lua_objlen(L, 2) : lua_gettop(L) - 1;
+
+	std::vector<uint16> vertexmap;
+	vertexmap.reserve(nargs);
+
+	for (int i = 0; i < nargs; i++)
+	{
+		if (is_table)
+		{
+			lua_rawgeti(L, 2, i + 1);
+			vertexmap.push_back(luaL_checkinteger(L, -1) - 1);
+			lua_pop(L, 1);
+		}
+		else
+			vertexmap.push_back(luaL_checkinteger(L, i + 2) - 1);
+	}
+
+	try
+	{
+		g->setElementArray(&vertexmap[0], vertexmap.size());
+	}
+	catch (love::Exception &e)
+	{
+		return luaL_error(L, "%s", e.what());
+	}
+	return 0;
+}
+
 static const luaL_Reg w_Geometry_functions[] =
 {
 	{ "getVertexCount", w_Geometry_getVertexCount },
@@ -125,6 +220,9 @@ static const luaL_Reg w_Geometry_functions[] =
 	{ "flip", w_Geometry_flip },
 	{ "setVertexColors", w_Geometry_setVertexColors },
 	{ "hasVertexColors", w_Geometry_hasVertexColors },
+	{ "getDrawMode", w_Geometry_getDrawMode },
+	{ "getVertexMap", w_Geometry_getVertexMap },
+	{ "setVertexMap", w_Geometry_setVertexMap },
 	{ 0, 0 }
 };