Add support for getting the max texture size

GL/private.h

@@ -9,6 +9,7 @@
 #define TRACE_ENABLED 0
 #define TRACE() if(TRACE_ENABLED) {fprintf(stderr, "%s\n", __func__);}
 
+#define MAX_TEXTURE_SIZE 1024
 
 typedef struct {
     unsigned int cmd[8];

GL/state.c

@@ -434,6 +434,9 @@ void APIENTRY glGetIntegerv(GLenum pname, GLint *params) {
         case GL_BLEND_DST:
             *params = BLEND_DFACTOR;
         break;
+        case GL_MAX_TEXTURE_SIZE:
+            *params = MAX_TEXTURE_SIZE;
+        break;
     default:
         _glKosThrowError(GL_INVALID_ENUM, "glGetIntegerv");
         _glKosPrintError();