check for multitexturing to use glActiveTexture call

git-svn-id: http://svn.net-core.org/repos/t-engine4@824 51575b47-30f0-44d4-a5cc-537603b46e54

src/main.c

@@ -51,8 +51,11 @@ bool exit_engine = FALSE;
 bool no_sound = FALSE;
 bool isActive = TRUE;
 bool tickPaused = FALSE;
+
+/* OpenGL capabilities */
 extern bool shaders_active;
 bool fbo_active;
+bool multitexture_active;
 
 /* Some lua stuff that's external but has no headers */
 int luaopen_mime_core(lua_State *L);
@@ -596,8 +599,10 @@ int main(int argc, char *argv[])
 	resizeWindow(WIDTH, HEIGHT);
 
 	// Get OpenGL capabilities
+	multitexture_active = glewIsSupported("GL_ARB_multitexture");
 	shaders_active = glewIsSupported("GL_ARB_shader_objects");
 	fbo_active = glewIsSupported("GL_EXT_framebuffer_object") || glewIsSupported("GL_ARB_framebuffer_object");
+	if (!multitexture_active) shaders_active = FALSE;
 
 	boot_lua(2, FALSE, argc, argv);
 

src/main.h

@@ -24,6 +24,7 @@
 extern int resizeWindow(int width, int height);
 extern void do_resize(int w, int h, bool fullscreen);
 extern bool fbo_active;
+extern bool multitexture_active;
 
 #endif
 

src/map.c

@@ -26,6 +26,7 @@
 #include "auxiliar.h"
 #include "types.h"
 #include "map.h"
+#include "main.h"
 #include "script.h"
 //#include "shaders.h"
 
@@ -423,7 +424,7 @@ void display_map_quad(map_type *map, int dx, int dy, map_object *m, int i, int j
 	if (m->shader) useShader(m->shader, i, j, a);
 	for (z = (!shaders_active) ? 0 : (m->nb_textures - 1); z >= 0; z--)
 	{
-		if (shaders_active) glActiveTexture(GL_TEXTURE0+z);
+		if (multitexture_active && shaders_active) glActiveTexture(GL_TEXTURE0+z);
 		glBindTexture(m->textures_is3d[z] ? GL_TEXTURE_3D : GL_TEXTURE_2D, m->textures[z]);
 	}
 	glBegin(GL_QUADS);