Trail of swag

CMakeLists.txt

@@ -33,6 +33,9 @@ set(SOURCES
 	src/player/draw.c
 	src/player/update.c
 	src/player/collide.c
+	src/trail/init.c
+	src/trail/update.c
+	src/trail/draw.c
 	src/input/init.c
 	src/input/update.c
 	src/particles/init.c
@@ -56,7 +59,7 @@ set(SOURCES
 
 set(ASSETS
 	assets/graphics/tileset.png
-	assets/graphics/burst.png
+	assets/graphics/trail.png
 	assets/graphics/coin-particle.png
 	assets/graphics/switch-particle.png
 	assets/graphics/switch-activated-particle.png

assets/graphics/fxconv-metadata.txt

@@ -2,11 +2,11 @@
 tileset.png:
   type: bopti-image
   name: bimg_tileset
-burst.png:
-  type: bopti-image
-  name: bimg_burst
 
 # libimg img_t
+trail.png:
+  type: libimg-image
+  name: img_trail
 coin-particle.png:
   type: libimg-image
   name: img_coin_particle

include/player.h

@@ -30,6 +30,7 @@ struct Player {
 	struct Particle idle_anim;
 	struct Particle jump_anim;
 	struct Particle walk_anim;
+	int trail_state;
 };
 
 /* used for collisions */

include/trail.h

@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/* Copyright (C) 2021 KikooDX */
+#pragma once
+
+#include "player.h"
+#include <libimg.h>
+
+#define TRAIL_LIFE           33
+#define TRAIL_FRAMES         3
+#define TRAIL_SIZE           10
+#define TRAIL_FRAME_DURATION (TRAIL_LIFE / TRAIL_FRAMES)
+
+struct Trail {
+	int x;
+	int y;
+	int life;
+	int frame;
+	color_t color;
+};
+
+void trail_init(void);
+void trail_update(struct Player player);
+void trail_draw(void);

src/main.c

@@ -10,6 +10,7 @@
 #include "particles.h"
 #include "player.h"
 #include "titlescreen.h"
+#include "trail.h"
 #include "transition.h"
 #include "zxcolors.h"
 #include <gint/clock.h>
@@ -33,6 +34,7 @@
 		if (fatal_error == -1)                                         \
 			PANIC(fatal_error_msg);                                \
 		particles_init();                                              \
+		trail_init();                                                  \
 		player = player_init();                                        \
 	} while (0);
 
@@ -52,7 +54,6 @@ main(void)
 	int timer;
 	int player_return_code;
 	int frameskip = 0;
-	int toskip = 0;
 	/* int level_pack_beaten; */
 	enum TransitionMode transition_previous_mode;
 	enum GameState game_state = TitleScreen;
@@ -89,7 +90,6 @@ main(void)
 	while (!keydown(KEY_EXIT)) {
 		/* skip render frames */
 		i = 1 + frameskip;
-		toskip = frameskip;
 		while (i-- > 0) {
 			/* frameskip adjustement */
 			if (has_ticked - 1 > frameskip)
@@ -126,6 +126,7 @@ main(void)
 				break;
 			case Playing:
 				if (transition.mode == TransitionNone) {
+					trail_update(player);
 					particles_update();
 					player_return_code =
 					    player_update(&player, input);
@@ -212,6 +213,7 @@ main(void)
 			break;
 		case Playing:
 			level_draw();
+			trail_draw();
 			particles_draw();
 			trail_draw();
 			player_draw(player);

src/particles/draw.c

@@ -29,7 +29,7 @@ particle_draw(struct Particle particle)
 		return;
 
 	/* fill image with transparent */
-	img_fill(transformed_img, IMG_ALPHA);
+	img_clear(transformed_img);
 
 	/* get frame subimage */
 	const img_t frame_simg =

src/player/draw.c

@@ -11,8 +11,6 @@
 
 extern struct Level level;
 
-extern bopti_image_t bimg_burst;
-
 void
 player_draw(struct Player player)
 {
@@ -25,10 +23,6 @@ player_draw(struct Player player)
 	/* draw animation */
 	particle_draw(anim);
 
-	/* draw burst */
-	if (player.air_state == AirRising && player.jumps_left < AIR_JUMPS)
-		dimage(player.x, player.y + PLAYER_HEIGHT, &bimg_burst);
-
 	/* print level name
 	 * this shouldn't be in player code */
 	dprint_opt(DWIDTH - 4, DHEIGHT, ZX_WHITE, C_NONE, DTEXT_RIGHT,

src/player/init.c

@@ -29,11 +29,12 @@ player_init(void)
 	    .jump_grace = 0,
 	    .jumps_left = 0,
 	    .air_state = AirNeutral,
+	    .trail_state = 0,
 	};
 
 	/* initialize animations */
 	player.blink_anim = particle_init(&img_player_blink, 0, 0, 10, 4, 0, 0);
-	player.idle_anim = particle_init(&img_player_idle, 0, 0, 10, 1, 1, 1);
+	player.idle_anim = particle_init(&img_player_idle, 0, 0, 10, 1, 1, 0);
 	player.jump_anim = particle_init(&img_player_jump, 0, 0, 8, 6, 0, 0);
 	player.walk_anim = particle_init(&img_player_walk, 0, 0, 12, 6, 1, 0);
 	player.anim = player.idle_anim;

src/player/update.c

@@ -94,6 +94,7 @@ player_update(struct Player *player, struct Input input)
 		}
 		/* air jump (burst) */
 		else {
+			player->trail_state = !player->trail_state;
 			player->jumps_left -= 1;
 			player->spd_y = AIR_JMP_SPD;
 			/* burst boost */

src/trail/draw.c

@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/* Copyright (C) 2021 KikooDX */
+
+#include "trail.h"
+#include <libimg.h>
+
+extern struct Trail trail[TRAIL_LIFE];
+extern const img_t img_trail;
+
+static void trail_atom_draw(struct Trail atom);
+
+void
+trail_draw(void)
+{
+	int i = TRAIL_LIFE;
+	while (i-- > 0)
+		trail_atom_draw(trail[i]);
+}
+
+static void
+trail_atom_draw(struct Trail atom)
+{
+	if (!atom.life)
+		return;
+
+	/* get frame subimage */
+	const img_t frame_simg = img_sub(img_trail, atom.frame * TRAIL_SIZE, 0,
+	                                 TRAIL_SIZE, TRAIL_SIZE);
+
+	/* tint the frame */
+	const img_t transformed_img = img_dye_create(frame_simg, atom.color);
+	/* check */
+	if (img_null(transformed_img))
+		return;
+
+	/* render image */
+	img_render_vram(transformed_img, atom.x, atom.y);
+
+	/* free */
+	img_destroy(transformed_img);
+}

src/trail/init.c

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/* Copyright (C) 2021 KikooDX */
+
+#include "trail.h"
+
+struct Trail trail[TRAIL_LIFE];
+
+void
+trail_init(void)
+{
+	int i = TRAIL_LIFE;
+	while (i-- > 0) {
+		trail[i] = (struct Trail){
+		    .x = 0,
+		    .y = 0,
+		    .life = 0,
+		    .frame = 0,
+		};
+	}
+}

src/trail/update.c

@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/* Copyright (C) 2021 KikooDX */
+
+#include "player.h"
+#include "trail.h"
+#include "zxcolors.h"
+#include <libimg.h>
+
+extern struct Trail trail[TRAIL_LIFE];
+
+static void trail_atom_update(struct Trail *atom);
+static void trail_create(int x, int y, color_t color);
+
+void
+trail_update(struct Player player)
+{
+	int i = TRAIL_LIFE;
+	color_t color = player.trail_state ? ZX_WHITE : ZX_GRAY;
+	/* update trail */
+	while (i-- > 1) {
+		trail[i] = trail[i - 1];
+		trail_atom_update(&trail[i]);
+	}
+	/* create atom */
+	trail_create(player.x + (PLAYER_WIDTH - TRAIL_SIZE) / 2,
+	             player.y + (PLAYER_HEIGHT - TRAIL_SIZE) / 2, color);
+}
+
+static void
+trail_atom_update(struct Trail *atom)
+{
+	if (!atom->life)
+		return;
+
+	atom->life -= 1;
+	if (!(atom->life % TRAIL_FRAME_DURATION))
+		atom->frame += 1;
+}
+
+static void
+trail_create(int x, int y, color_t color)
+{
+	trail[0].x = x;
+	trail[0].y = y;
+	trail[0].life = TRAIL_LIFE;
+	trail[0].frame = 0;
+	trail[0].color = color;
+}