feat: initial revision

src/main.c

@@ -1,23 +1,462 @@
 /*
-Raylib example file.
+Shooting arrows - ya know
-This is an example main file for a simple raylib project.
-Use this as a starting point or replace it with your code.
-
-by Jeffery Myers is marked with CC0 1.0. To view a copy of this license, visit https://creativecommons.org/publicdomain/zero/1.0/
-
 */
 
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+
 #include "raylib.h"
+#include "resource_dir.h"
 
-#include "resource_dir.h"	// utility header for SearchAndSetResourceDir
+const float G = 458.0;
+const float attritionCoefficient = 95.0;
+const int archerSize = 10;
+const float archerSpeed = 96.0;
+const float maxBowTension = 921.0;
+const float bowTensionSpeed = 12.0;
 
-int main ()
+const float spacing = 16;
+const float bowTensionIndicatorWidth = 360;
+const float bowTensionIndicatorHeight = 40;
+
+const float arrowLength = 20.0f;
+const int groundHeight = 40;
+
+#define MAX_BLOOD_PARTICLES 800
+
+// Utility function to map a value from one range to another
+float map(float value, float fromLow, float fromHigh, float toLow, float toHigh)
+{
+	return toLow + (toHigh - toLow) * (value - fromLow) / (fromHigh - fromLow);
+}
+
+// Utility function to normalize a Vector2
+Vector2 normalized(Vector2 v)
+{
+	float len = sqrtf(v.x * v.x + v.y * v.y);
+	if (len == 0.0f)
+	{
+		Vector2 zero = {0.0f, 0.0f};
+		return zero;
+	}
+	Vector2 n = {v.x / len, v.y / len};
+	return n;
+}
+
+typedef struct Target Target;
+typedef struct Arrow Arrow;
+
+struct Arrow
+{
+	Vector2 position;
+	Vector2 speed;
+	Vector2 acceleration;
+	Vector2 direction;
+	bool stuck;
+	Target *hitTarget;
+};
+
+typedef struct ArrowNode ArrowNode;
+
+struct ArrowNode
+{
+	Arrow *data;
+	ArrowNode *prev;
+	ArrowNode *next;
+};
+
+// Bleed pattern: alternating durations of squirt (spawn particles) and pause
+// {squirt, pause, squirt, pause, squirt, pause, squirt,..., 0} — 0 marks end
+#define BLEED_PHASES 18
+const float bleedPattern[BLEED_PHASES] = {0.08f, 0.06f, 0.38f, 0.25f, 0.08f, 2.06f, 0.38f, 0.25f, 0.10f, 1.06f, 0.08f, 0.3f, 2.2f, 0.4f, 1.1f, 0.9f, 0.8f, 0.0f};
+// even indices = squirt, odd indices = pause, last 0 = done
+
+typedef struct
+{
+	Vector2 position;
+	Vector2 velocity;
+	float lifetime;
+	float maxLifetime;
+	bool active;
+} BloodParticle;
+
+BloodParticle bloodParticles[MAX_BLOOD_PARTICLES];
+
+void spawn_blood(Vector2 origin, Vector2 direction, int count)
+{
+	for (int i = 0; i < MAX_BLOOD_PARTICLES && count > 0; i++)
+	{
+		if (!bloodParticles[i].active)
+		{
+			bloodParticles[i].active = true;
+			bloodParticles[i].position = origin;
+			// base direction is opposite to the arrow's flight
+			float baseAngle = atan2f(-direction.y, -direction.x);
+			// spread within ~90 degrees of the opposite direction
+			float spread = ((float)GetRandomValue(-45, 45)) * DEG2RAD;
+			float angle = baseAngle + spread;
+			float speed = (float)GetRandomValue(0, 320);
+			bloodParticles[i].velocity.x = cosf(angle) * speed;
+			bloodParticles[i].velocity.y = sinf(angle) * speed;
+			bloodParticles[i].maxLifetime = 0.4f + (float)GetRandomValue(10, 475) / 100.0f;
+			bloodParticles[i].lifetime = bloodParticles[i].maxLifetime;
+			count--;
+		}
+	}
+}
+
+void update_blood(float deltaTime)
+{
+	for (int i = 0; i < MAX_BLOOD_PARTICLES; i++)
+	{
+		if (!bloodParticles[i].active)
+			continue;
+
+		bloodParticles[i].lifetime -= deltaTime;
+		if (bloodParticles[i].lifetime <= 0)
+		{
+			bloodParticles[i].active = false;
+			continue;
+		}
+
+		bloodParticles[i].velocity.y += G * 0.5f * deltaTime;
+		bloodParticles[i].position.x += bloodParticles[i].velocity.x * deltaTime;
+		bloodParticles[i].position.y += bloodParticles[i].velocity.y * deltaTime;
+	}
+}
+
+void draw_blood(void)
+{
+	for (int i = 0; i < MAX_BLOOD_PARTICLES; i++)
+	{
+		if (!bloodParticles[i].active)
+			continue;
+
+		float alpha = bloodParticles[i].lifetime / bloodParticles[i].maxLifetime;
+		unsigned char a = (unsigned char)(alpha * 255);
+		Color c = {200, 0, 0, a};
+		float size = 2.0f + alpha * 2.0f;
+		DrawRectangle(
+			(int)(bloodParticles[i].position.x - size / 2),
+			(int)(bloodParticles[i].position.y - size / 2),
+			(int)size, (int)size, c);
+	}
+}
+
+struct Target
+{
+	Vector2 position;
+	Vector2 speed;
+	bool bleeding;
+	bool grounded;
+	int bleedPhase;
+	float bleedTimer;
+};
+
+typedef struct TargetNode TargetNode;
+
+struct TargetNode
+{
+	Target *data;
+	TargetNode *prev;
+	TargetNode *next;
+};
+
+void add_target(TargetNode *head, Vector2 position)
+{
+	TargetNode *el = head;
+	while (el->next)
+	{
+		el = el->next;
+	}
+
+	Target *t = malloc(sizeof(Target));
+	t->position = position;
+	t->speed.x = 0;
+	t->speed.y = 0;
+	t->bleeding = false;
+	t->grounded = false;
+	t->bleedPhase = 0;
+	t->bleedTimer = 0;
+
+	TargetNode *newNode = (TargetNode *)malloc(sizeof(TargetNode));
+	newNode->data = t;
+	newNode->prev = el;
+	newNode->next = NULL;
+
+	el->next = newNode;
+}
+
+void remove_target(TargetNode *node)
+{
+	node->prev->next = node->next;
+	if (node->next)
+		node->next->prev = node->prev;
+	free(node->data);
+	free(node);
+}
+
+void fire_arrow(ArrowNode *head, Vector2 origin, Vector2 acceleration)
+{
+	if (!head)
+	{
+		TraceLog(LOG_ERROR, "Cannot fire arrow: head pointer is NULL");
+		return;
+	}
+
+	ArrowNode *el = head;
+	while (el->next)
+	{
+		el = el->next;
+	}
+
+	Arrow *a = malloc(sizeof(Arrow));
+	a->position.x = origin.x;
+	a->position.y = origin.y;
+	a->speed.x = acceleration.x;
+	a->speed.y = acceleration.y;
+	a->acceleration.x = 0;
+	a->acceleration.y = 0;
+	a->direction = normalized(a->speed);
+	a->stuck = false;
+	a->hitTarget = NULL;
+
+	ArrowNode *newNode = (ArrowNode *)malloc(sizeof(ArrowNode));
+	newNode->data = a;
+	newNode->prev = el;
+	newNode->next = NULL;
+
+	el->next = newNode;
+}
+
+void update_arrows(ArrowNode *head, TargetNode *targets, Texture targetTex, float deltaTime, float attrition)
+{
+	Rectangle groundRect = {.x = 0, .y = GetScreenHeight() - groundHeight, .width = GetScreenWidth(), .height = groundHeight};
+
+	ArrowNode *el = head->next;
+	while (el != NULL)
+	{
+		Arrow *a = el->data;
+
+		// skip stuck arrows
+		if (a->stuck)
+		{
+			el = el->next;
+			continue;
+		}
+
+		a->speed.x += a->acceleration.x * deltaTime;
+		a->speed.y += a->acceleration.y * deltaTime;
+
+		// apply gravity directly to speed
+		a->speed.y += G * deltaTime;
+
+		a->position.x += a->speed.x * deltaTime;
+		a->position.y += a->speed.y * deltaTime;
+
+		// update flight direction
+		a->direction = normalized(a->speed);
+
+		// to simulate attrition will scale down the acceleration by a constant
+		float decay = powf(attrition, deltaTime);
+		a->acceleration.x *= decay;
+		a->acceleration.y *= decay;
+
+		// check for target collisions
+		TargetNode *tEl = targets->next;
+		while (tEl != NULL)
+		{
+			Target *t = tEl->data;
+			if (t->bleeding)
+			{
+				tEl = tEl->next;
+				continue;
+			}
+			Rectangle targetRect = {t->position.x, t->position.y, (float)targetTex.width, (float)targetTex.height};
+			if (CheckCollisionPointRec(a->position, targetRect))
+			{
+				t->bleeding = true;
+				t->bleedPhase = 0;
+				t->bleedTimer = bleedPattern[0];
+
+				// penetrate into the target proportionally to hit speed
+				float hitSpeed = sqrtf(a->speed.x * a->speed.x + a->speed.y * a->speed.y);
+				float maxPenetration = arrowLength * 1.1f;
+				float penetration = (hitSpeed / maxBowTension) * maxPenetration;
+				a->position.x += a->direction.x * penetration;
+				a->position.y += a->direction.y * penetration;
+
+				a->acceleration.x = a->acceleration.y = a->speed.x = a->speed.y = 0;
+				a->stuck = true;
+				a->hitTarget = t;
+				TraceLog(LOG_INFO, "Target hit!");
+				break;
+			}
+			tEl = tEl->next;
+		}
+
+		if (a->stuck)
+		{
+			el = el->next;
+			continue;
+		}
+
+		// check for ground collision
+		if (CheckCollisionPointRec(a->position, groundRect))
+		{
+			a->position.y = GetScreenHeight() - groundHeight;
+			a->acceleration.x = a->acceleration.y = a->speed.x = a->speed.y = 0;
+			a->stuck = true;
+		}
+
+		// if arrow went offscreen, remove it
+		if (
+			(a->position.x > GetScreenWidth() || a->position.x < 0) ||
+			a->position.y > GetScreenHeight())
+		{
+			el->prev->next = el->next;
+			if (el->next)
+				el->next->prev = el->prev;
+
+			ArrowNode *orphan = el;
+
+			el = el->next;
+			free(orphan->data);
+			free(orphan);
+
+			TraceLog(LOG_INFO, "Removing arrow");
+		}
+		else
+		{
+			el = el->next;
+		}
+	}
+}
+
+void remove_arrow(ArrowNode *node)
+{
+	node->prev->next = node->next;
+	if (node->next)
+		node->next->prev = node->prev;
+	free(node->data);
+	free(node);
+}
+
+void update_targets(TargetNode *targets, ArrowNode *arrows, Texture targetTex, float deltaTime)
+{
+	TargetNode *tEl = targets->next;
+	while (tEl != NULL)
+	{
+		Target *t = tEl->data;
+		if (!t->bleeding)
+		{
+			tEl = tEl->next;
+			continue;
+		}
+
+		// apply gravity and move the target while falling
+		if (!t->grounded)
+		{
+			t->speed.y += G * deltaTime;
+			float dx = t->speed.x * deltaTime;
+			float dy = t->speed.y * deltaTime;
+			t->position.x += dx;
+			t->position.y += dy;
+
+			float groundY = GetScreenHeight() - groundHeight - targetTex.height;
+			if (t->position.y >= groundY)
+			{
+				dy -= (t->position.y - groundY);
+				t->position.y = groundY;
+				t->speed.x = 0;
+				t->speed.y = 0;
+				t->grounded = true;
+			}
+
+			// move stuck arrows along with the target
+			ArrowNode *aEl = arrows->next;
+			while (aEl != NULL)
+			{
+				if (aEl->data->hitTarget == t)
+				{
+					aEl->data->position.x += dx;
+					aEl->data->position.y += dy;
+				}
+				aEl = aEl->next;
+			}
+		}
+
+		t->bleedTimer -= deltaTime;
+		if (t->bleedTimer > 0)
+		{
+			// during squirt phases (even indices), spawn particles
+			if (t->bleedPhase % 2 == 0)
+			{
+				Vector2 center = {
+					t->position.x + targetTex.width / 2.0f,
+					t->position.y + targetTex.height / 2.0f};
+
+				ArrowNode *aEl = arrows->next;
+				while (aEl != NULL)
+				{
+					ArrowNode *aNext = aEl->next;
+					if (aEl->data->hitTarget == t)
+					{
+						spawn_blood(aEl->data->position, aEl->data->direction, MAX_BLOOD_PARTICLES / 2);
+					}
+					aEl = aNext;
+				}
+			}
+			tEl = tEl->next;
+		}
+		else
+		{
+			// advance to next phase
+			t->bleedPhase++;
+			if (t->bleedPhase >= BLEED_PHASES || bleedPattern[t->bleedPhase] == 0.0f)
+			{
+				// remove arrows that hit this target
+				ArrowNode *aEl = arrows->next;
+				while (aEl != NULL)
+				{
+					ArrowNode *aNext = aEl->next;
+					if (aEl->data->hitTarget == t)
+					{
+						remove_arrow(aEl);
+					}
+					aEl = aNext;
+				}
+
+				// animation done, remove target and spawn a new one
+				TargetNode *dead = tEl;
+				tEl = tEl->next;
+				remove_target(dead);
+
+				Vector2 newPos = {
+					(float)GetRandomValue(0, GetScreenWidth() - targetTex.width),
+					(float)GetRandomValue(0, GetScreenHeight() / 2)};
+				add_target(targets, newPos);
+
+				TraceLog(LOG_INFO, "Target removed after bleeding, new target spawned");
+			}
+			else
+			{
+				t->bleedTimer = bleedPattern[t->bleedPhase];
+				tEl = tEl->next;
+			}
+		}
+	}
+}
+
+int main()
 {
 	// Tell the window to use vsync and work on high DPI displays
-	SetConfigFlags(FLAG_VSYNC_HINT | FLAG_WINDOW_HIGHDPI);
+	SetConfigFlags(FLAG_VSYNC_HINT | FLAG_WINDOW_HIGHDPI | FLAG_WINDOW_RESIZABLE);
 
 	// Create the window and OpenGL context
-	InitWindow(1280, 800, "Hello Raylib");
+	InitWindow(1280, 800, "Archer");
 
 	// Utility function from resource_dir.h to find the resources folder and set it as the current working directory so we can load from it
 	SearchAndSetResourceDir("resources");
@@ -25,26 +464,175 @@ int main ()
 	// Load a texture from the resources directory
 	Texture wabbit = LoadTexture("wabbit_alpha.png");
 
+	int screenWidth = GetScreenWidth();
+	int screenHeight = GetScreenHeight();
+
+	Vector2 mousePosition = {0, 0};
+	char coords[200];
+
+	bool trajectoryVisible = false;
+
+	Vector2 archerPosition = {screenWidth / 2 - archerSize / 2, screenHeight - groundHeight - archerSize};
+
+	float bowTension = 0.0;
+
+	ArrowNode *head = (ArrowNode *)calloc(1, sizeof(ArrowNode));
+
+	TargetNode *targets = (TargetNode *)calloc(3, sizeof(TargetNode));
+
+	for (int i = 0; i < 3; i++)
+	{
+		// spawn targets at a random position in the top region
+		Vector2 targetPos = {
+			(float)GetRandomValue(0, screenWidth - wabbit.width),
+			(float)GetRandomValue(0, screenHeight / 3)};
+		add_target(targets, targetPos);
+	}
+
+	float dt = 0;
+
 	// game loop
 	while (!WindowShouldClose()) // run the loop until the user presses ESCAPE or presses the Close button on the window
 	{
+		dt = GetFrameTime();
+
+		if (IsWindowResized())
+		{
+			screenWidth = GetScreenWidth();
+			screenHeight = GetScreenHeight();
+		}
+
+		mousePosition = GetMousePosition();
+		sprintf(coords, "(x=%1.0f, y=%1.0f)", mousePosition.x, mousePosition.y);
+
+		float tensionRate = -3.0;
+		if (IsMouseButtonDown(MOUSE_BUTTON_LEFT))
+		{
+			tensionRate = 1.0;
+		}
+
+		bowTension += bowTensionSpeed * tensionRate;
+		if (bowTension < 0)
+		{
+			bowTension = 0;
+		}
+		if (bowTension > maxBowTension)
+		{
+			bowTension = maxBowTension;
+		}
+
+		// Pressing the right mouse button releases the bow istantly
+		if (IsMouseButtonPressed(MOUSE_BUTTON_RIGHT))
+		{
+			TraceLog(LOG_INFO, "Arrow launched");
+
+			Vector2 dir = {mousePosition.x - archerPosition.x, mousePosition.y - archerPosition.y};
+			Vector2 direction = normalized(dir);
+			Vector2 force = {direction.x * bowTension, direction.y * bowTension};
+			fire_arrow(head, archerPosition, force);
+			bowTension = 0;
+		}
+
+		if (IsKeyPressed(KEY_T))
+		{
+			trajectoryVisible = !trajectoryVisible;
+			TraceLog(LOG_INFO, "Toggling trajectory indicators");
+		}
+
+		if (IsKeyDown(KEY_A))
+		{
+			archerPosition.x -= archerSpeed * dt;
+		}
+
+		if (IsKeyDown(KEY_D))
+		{
+			archerPosition.x += archerSpeed * dt;
+		}
+
+		update_arrows(head, targets, wabbit, dt, attritionCoefficient);
+		update_targets(targets, head, wabbit, dt);
+		update_blood(dt);
+
 		// drawing
 		BeginDrawing();
 
 		// Setup the back buffer for drawing (clear color and depth buffers)
 		ClearBackground(BLACK);
 
-		// draw some text using the default font
+		// Draw ground
-		DrawText("Hello Raylib", 200,200,20,WHITE);
+		DrawRectangle(0, screenHeight - groundHeight, screenWidth, groundHeight, BROWN);
 
-		// draw our texture to the screen
+		// draw targets
-		DrawTexture(wabbit, 400, 200, WHITE);
+		TargetNode *drawTarget = targets->next;
+		while (drawTarget != NULL)
+		{
+			Target *t = drawTarget->data;
+			DrawTexture(wabbit, (int)t->position.x, (int)t->position.y, WHITE);
+			drawTarget = drawTarget->next;
+		}
+
+		// draw blood particles
+		draw_blood();
+
+		// for now the archer will be a simple square
+		DrawRectangle(archerPosition.x, archerPosition.y, archerSize, archerSize, GREEN);
+
+		// draw arrows
+		ArrowNode *drawEl = head->next;
+		while (drawEl != NULL)
+		{
+			Arrow *a = drawEl->data;
+			Vector2 dir = a->direction;
+			Vector2 tail = {a->position.x - dir.x * arrowLength, a->position.y - dir.y * arrowLength};
+			DrawLineEx(tail, a->position, 2.0f, YELLOW);
+			drawEl = drawEl->next;
+		}
+
+		if (trajectoryVisible)
+		{
+			// aim hints
+			Vector2 startY = {0, mousePosition.y};
+			DrawLineDashed(startY, mousePosition, 4, 8, GRAY);
+
+			Vector2 startX = {mousePosition.x, screenHeight};
+			DrawLineDashed(startX, mousePosition, 4, 8, GRAY);
+
+			Vector2 bowOrigin = {archerPosition.x + archerSize / 2, archerPosition.y + archerSize / 2};
+			DrawLineDashed(bowOrigin, mousePosition, 4, 8, GRAY);
+
+			// targeting coordinates
+			DrawText(coords, screenWidth - bowTensionIndicatorWidth - spacing, bowTensionIndicatorHeight + 2 * spacing, 24, WHITE);
+		}
+
+		// Tension indicator
+		DrawRectangleLines(screenWidth - bowTensionIndicatorWidth - spacing, spacing, bowTensionIndicatorWidth, bowTensionIndicatorHeight, WHITE);
+		DrawRectangle(screenWidth - bowTensionIndicatorWidth - spacing, spacing, map(bowTension, 0, maxBowTension, 0, bowTensionIndicatorWidth), bowTensionIndicatorHeight, WHITE);
 
 		// end the frame and get ready for the next one  (display frame, poll input, etc...)
 		EndDrawing();
 	}
 
 	// cleanup
+	// free arrow linked list
+	ArrowNode *el = head;
+	while (el != NULL)
+	{
+		ArrowNode *next = el->next;
+		free(el->data);
+		free(el);
+		el = next;
+	}
+
+	// free target linked list
+	TargetNode *tEl = targets;
+	while (tEl != NULL)
+	{
+		TargetNode *next = tEl->next;
+		free(tEl->data);
+		free(tEl);
+		tEl = next;
+	}
+
 	// unload our texture so it can be cleaned up
 	UnloadTexture(wabbit);