winter is comming: brace yourself

src/scene.c

@@ -0,0 +1,80 @@
+#include "renderer.h"
+#include "scene.h"
+
+static int compartSort(const SceneObject_t * a, const SceneObject_t * b) {
+	return a->renderObj.z - b->renderObj.z;
+}
+
+void scene_render(Scene_t * scene) {
+	MonitorSize_t monitorSize = renderer_getMonitorSize();
+	int minX = scene->x - CAMERA_WIDTH/2;
+	int minY = scene->y - CAMERA_HEIGHT/2;
+	int maxX = scene->x - CAMERA_WIDTH/2;
+	int maxY = scene->y - CAMERA_HEIGHT/2;
+
+	for(int i = 0; i < scene->objectCount; i++) {
+		SceneObject_t * object = &scene->objects[i];
+		if(object->x > minX && object->x < maxX && object->y > minY && object->y < maxY) {
+			int x = (object->x - minX) / CAMERA_WIDTH;
+			int y = (object->y - minY) / CAMERA_HEIGHT;
+			//the object is to be rendered
+
+			SDL_Rect rect = {
+				round(x * monitorSize.width) ,
+				round(y * monitorSize.height),
+				round(object->renderObj.width * monitorSize.width),
+				round(object->renderObj.height * monitorSize.height)
+			};
+
+			int error = SDL_RenderCopyEx(renderer, object->cache, NULL, &rect, object->renderObj.angle_degre, NULL, SDL_FLIP_NONE);
+			if(error != 0) {
+				fprintf(stderr, "Render error in object %d with error %s\n", object->id, SDL_GetError());
+				exit(1);
+			}
+		}
+	}
+}
+
+static void buildCache(SceneObject_t * object) {
+	SDL_Texture * texture = SDL_CreateTextureFromSurface(renderer, object->renderObj.surface);
+	if(texture == NULL) {
+		fprintf(stderr, "Error while creating texture %s is_null: %d\n", SDL_GetError(), object->renderObj.surface == NULL);
+		exit(1);
+	}
+	SDL_SetTextureBlendMode(texture, SDL_BLENDMODE_BLEND);
+	object->cache = texture;
+}
+
+RenderId_t scene_addRenderObject(Scene_t * scene, RenderObject_t object, int x, int y) {
+	RenderId_t itemId = scene->objectCount++;
+
+	SceneObject_t item = {
+		x, y,
+		object,
+		NULL,
+		itemId
+	};
+
+	buildCache(&item);
+
+	scene->objects[itemId] = item;
+	//the objects are sorted
+	qsort(scene->objects, scene->objectCount, sizeof(RenderObject_t), (__compar_fn_t)compartSort);
+	return itemId;
+}
+
+void scene_removeRenderObject(Scene_t * scene, RenderId_t id) {
+	bool found = false;
+	for(int i = 0; i < scene->objectCount - 1; i++) {
+		if(scene->objects[i].id == id) {
+			SDL_FreeSurface(scene->objects[i].renderObj.surface);
+			if(scene->objects[i].cache != NULL) {
+				SDL_DestroyTexture(scene->objects[i].cache);
+			}
+		}
+		if(found) {
+			scene->objects[i] = scene->objects[i + 1];
+		}
+	}
+	scene->objectCount--;
+}