From 0a4c1fd15440e9a29daad14263758bd5a65a438c Mon Sep 17 00:00:00 2001
From: Klemen Plestenjak <plestenjak.klemen@gmail.com>
Date: Tue, 23 Jan 2024 23:09:08 +0100
Subject: [PATCH] Only render objects on screen

---
 CMakeLists.txt  |  1 +
 game/main.c     | 19 ++++++++++++++-----
 game/map_init.c | 14 +++++++++++++-
 game/utils.h    | 21 +++++++++++++++++++++
 4 files changed, 49 insertions(+), 6 deletions(-)
 create mode 100644 game/utils.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6236525..5461553 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -41,6 +41,7 @@ add_executable(PixelDefense
         game/sounds.h
         game/ui_widgets.c
         game/ui_widgets.h
+        game/utils.h
 )
 
 
diff --git a/game/main.c b/game/main.c
index 6dcf625..268077d 100644
--- a/game/main.c
+++ b/game/main.c
@@ -12,6 +12,7 @@
 #include "map_layers.h"
 #include "buildings.h"
 #include "ui_widgets.h"
+#include "utils.h"
 
 #include "pathfinding.h"
 #include "sounds.h"
@@ -376,8 +377,9 @@ static void renderGame(Game *game, float dt) {
     i32 numDraws = ecs_query_entity_count(game->drawQuery);
     DrawData *drawData = bzStackAlloc(&game->stackAlloc, numDraws * sizeof(*drawData));
     ecs_iter_t it = ecs_query_iter(ECS, game->drawQuery);
-    ecs_entity_t worker = 0;
     i32 drawIdx = 0;
+    Camera2D camera = game->camera;
+    Rectangle camBounds = getCameraBounds(camera);
     while (ecs_iter_next(&it)) {
         Position *p = ecs_field(&it, Position, 1);
         Size *s = ecs_field(&it, Size, 2);
@@ -385,12 +387,17 @@ static void renderGame(Game *game, float dt) {
         TextureRegion *t = ecs_field(&it, TextureRegion, 4);
         for (i32 i = 0; i < it.count; i++) {
             Rectangle dst = {p[i].x, p[i].y, s[i].x, s[i].y};
-            if (dst.width == 10 && dst.height == 10) {
-                worker = it.entities[i];
-            }
             Vector2 origin = {dst.width * 0.5f, dst.height};
             dst.x += origin.x - dst.width * 0.5f;
             dst.y += origin.y - dst.height * 0.5f;
+            Rectangle collider = {
+                    p[i].x - s[i].x * 0.5f,
+                    p[i].y - s[i].y * 0.5f,
+                    .width = s[i].x,
+                    .height = s[i].y
+            };
+            if (!CheckCollisionRecs(camBounds, collider))
+                continue;
             Rectangle src = t[i].rec;
             // Fixes texture bleeding issue
             src.x += 0.01f;
@@ -417,7 +424,7 @@ static void renderGame(Game *game, float dt) {
             drawData[drawIdx++] = draw;
         }
     }
-    BZ_ASSERT(drawIdx == numDraws);
+    numDraws = drawIdx;
     qsort(drawData, numDraws, sizeof(*drawData), cmpDrawData);
 
     Texture2D tex = game->tileset.tiles;
@@ -450,6 +457,7 @@ static void renderGame(Game *game, float dt) {
     elapsed += dt * 2;
     elapsed = Clamp(elapsed, 0, 1.0f);
     attack = false;
+#if 0
     if (worker && false) {
         Position *pos = ecs_get_mut(ECS, worker, Position);
         DrawCircle(pos->x, pos->y, 2.0f, BLUE);
@@ -463,6 +471,7 @@ static void renderGame(Game *game, float dt) {
         *rot = targetRot * bzEase(BZ_EASE_IN_BACK, elapsed);
         bzLogInfo("%.2f", Vector2Angle(*pos, lockedTarget) * RAD2DEG);
     }
+#endif
 
     ecs_progress(ECS, dt);
     ecs_enable(ECS, renderDebugPathSystem, game->debug.drawPath);
diff --git a/game/map_init.c b/game/map_init.c
index 9bbca07..ac55d71 100644
--- a/game/map_init.c
+++ b/game/map_init.c
@@ -7,6 +7,7 @@
 #include "entity_factory.h"
 #include "game_state.h"
 #include "map_layers.h"
+#include "utils.h"
 
 bool initGameObjectsLayer(BzTileMap *map, BzTileObjectGroup *objectGroup) {
     Game *game = ecs_singleton_get_mut(ECS, Game);
@@ -186,6 +187,10 @@ void terrainRender(BzTileMap *map, BzTileLayer *layer) {
     static f32 elapsed = 0.0f;
     elapsed += GetFrameTime();
 
+    const Game *game = ecs_singleton_get(ECS, Game);
+    Camera2D camera = game->camera;
+    Rectangle camBounds = getCameraBounds(camera);
+
     for (i32 y = 0; y < layer->height; y++) {
         for (i32 x = 0; x < layer->width; x++) {
             BzTile tile = bzTileLayerGetTile(layer, x, y);
@@ -198,7 +203,14 @@ void terrainRender(BzTileMap *map, BzTileLayer *layer) {
                     tile = terrainGetAnimationFrame(tile, frameIdx).frame;
                 }
                 Rectangle rec = bzTilesetGetTileRegion(tileset, tile);
-                DrawTextureRec(tileset->tiles, rec, drawPos, WHITE);
+                Rectangle bounds = {
+                        drawPos.x,
+                        drawPos.y,
+                        tileset->tileWidth,
+                        tileset->tileHeight
+                };
+                if (CheckCollisionRecs(camBounds, bounds))
+                    DrawTextureRec(tileset->tiles, rec, drawPos, WHITE);
             }
             drawPos.x += (float) tileset->tileWidth;
         }
diff --git a/game/utils.h b/game/utils.h
new file mode 100644
index 0000000..3421d5f
--- /dev/null
+++ b/game/utils.h
@@ -0,0 +1,21 @@
+#ifndef PIXELDEFENSE_UTILS_H
+#define PIXELDEFENSE_UTILS_H
+
+#include <raylib.h>
+#include <breeze.h>
+
+static Rectangle getCameraBounds(Camera2D camera) {
+    Rectangle bounds = {
+            .x = camera.target.x,
+            .y = camera.target.y,
+            .width = GetScreenWidth() / camera.zoom,
+            .height = GetScreenHeight() / camera.zoom,
+    };
+    //bounds.width *= 0.8f;
+    //bounds.height *= 0.8f;
+    bounds.x -= bounds.width * 0.5f;
+    bounds.y -= bounds.height * 0.5f;
+    return bounds;
+}
+
+#endif //PIXELDEFENSE_UTILS_H