partially done work on total source tree rework, separation of engine context and game context, generalization of renderer for different backends as well as web platform target

include/twn_context.h

@@ -0,0 +1,38 @@
+#ifndef TWN_CONTEXT_H
+#define TWN_CONTEXT_H
+
+#include "twn_input.h"
+#include "twn_engine_api.h"
+
+#include <stdbool.h>
+#include <stdint.h>
+
+
+typedef struct context {
+    struct input_state input;
+
+    int64_t delta_time; /* preserves real time frame delta with no manipilation */
+    uint64_t tick_count;
+
+    /* set just once on startup */
+    uint64_t random_seed;
+
+    /* this should be a multiple of TICKS_PER_SECOND */
+    /* use it to simulate low framerate (e.g. at 60 tps, set to 2 for 30 fps) */
+    /* it can be changed at runtime; any resulting logic anomalies are bugs */
+    unsigned int update_multiplicity;
+    int window_w;
+    int window_h;
+
+    /* you may read from and write to these from game code */
+    void *udata;
+
+    bool debug;
+    bool is_running;
+    bool window_size_has_changed;
+    bool initialization_needed;
+} t_ctx;
+
+TWN_API extern t_ctx ctx;
+
+#endif