Now I can attach arbitrary shaders to sprites based on things that happen in the world.

components.hpp

@@ -4,6 +4,7 @@
 #include "dinkyecs.hpp"
 #include "point.hpp"
 #include <SFML/Graphics/Rect.hpp>
+#include <SFML/Graphics/Shader.hpp>
 #include <SFML/System/Vector2.hpp>
 #include <functional>
 #include <optional>
@@ -15,6 +16,11 @@
 namespace components {
   using namespace nlohmann;
 
+  struct SpriteEffect {
+    int frames;
+    std::shared_ptr<sf::Shader> effect;
+  };
+
   struct Position {
     Point location;
   };

raycaster.cpp

@@ -9,6 +9,7 @@
 #include <numbers>
 #include "components.hpp"
 #include "textures.hpp"
+#include "systems.hpp"
 
 using namespace fmt;
 using std::make_unique;
@@ -180,10 +181,9 @@ void Raycaster::sprite_casting(sf::RenderTarget &target) {
       // float level = sqrt(rec.first);
       float level = lights[sprite_pos.location.y][sprite_pos.location.x] * PERCENT;
 
-      shared_ptr<sf::Shader> effect = nullptr;
+      shared_ptr<sf::Shader> effect = System::sprite_effect($level, rec.second);
 
-      if(rec.second == aiming_at) {
+      if(effect) {
-        effect = $flame;
         apply_sprite_effect(effect, sprite_width, sprite_height);
       } else {
         effect = $brightness;
@@ -411,7 +411,4 @@ void Raycaster::update_level(GameLevel level) {
 
 void Raycaster::init_shaders() {
   $brightness = shaders::get("rayview_sprites");
-  $brightness->setUniform("source", sf::Shader::CurrentTexture);
-  $flame = shaders::get("flame");
-  $flame->setUniform("source", sf::Shader::CurrentTexture);
 }

raycaster.hpp

@@ -13,7 +13,6 @@ struct Raycaster {
   int $pitch=0;
   sf::Clock $clock;
   std::shared_ptr<sf::Shader> $brightness = nullptr;
-  std::shared_ptr<sf::Shader> $flame = nullptr;
   double $pos_x = 0;
   double $pos_y = 0;
 

shaders.cpp

@@ -7,17 +7,25 @@
 #include <memory>
 
 namespace shaders {
-using std::shared_ptr, std::make_shared;
+  using std::shared_ptr, std::make_shared;
 
-static ShaderManager SMGR;
+  static ShaderManager SMGR;
-static bool INITIALIZED = false;
+  static bool INITIALIZED = false;
-static int VERSION = 0;
+  static int VERSION = 0;
 
-bool load_shader(std::string name, nlohmann::json& settings) {
+  inline void configure_shader_defaults(std::shared_ptr<sf::Shader> ptr) {
+    ptr->setUniform("source", sf::Shader::CurrentTexture);
+  }
+
+  bool load_shader(std::string name, nlohmann::json& settings) {
     std::string file_name = settings["file_name"];
     auto ptr = std::make_shared<sf::Shader>();
     bool good = ptr->loadFromFile(file_name, sf::Shader::Type::Fragment);
-    if(good) SMGR.shaders.try_emplace(name, name, file_name, ptr);
+
+    if(good) {
+      configure_shader_defaults(ptr);
+      SMGR.shaders.try_emplace(name, name, file_name, ptr);
+    }
     return good;
   }
 

systems.cpp

@@ -15,6 +15,7 @@
 #include "rituals.hpp"
 #include "battle.hpp"
 #include <iostream>
+#include "shaders.hpp"
 
 using std::string;
 using namespace fmt;
@@ -176,6 +177,7 @@ void System::death(GameLevel &level, components::ComponentMap& components) {
     world.remove<Personality>(ent);
     world.remove<ai::EntityAI>(ent);
     world.remove<Animation>(ent);
+    world.remove<SpriteEffect>(ent);
 
     if(auto snd = world.get_if<Sound>(ent)) {
       sound::stop(snd->attack);
@@ -235,6 +237,11 @@ void System::combat(GameLevel &level) {
       player_combat.attack(enemy.combat), 0
     };
 
+    if(result.player_did > 0) {
+      auto effect = shaders::get("flame");
+      world.set<SpriteEffect>(enemy.entity, {100, effect});
+    }
+
     if(enemy.ai.wants_to("kill_enemy")) {
       result.enemy_did = enemy.combat.attack(player_combat);
       animate_entity(world, enemy.entity);
@@ -390,3 +397,20 @@ std::wstring System::draw_map(GameLevel level, size_t view_x, size_t view_y, int
 
   return result;
 }
+
+
+std::shared_ptr<sf::Shader> System::sprite_effect(GameLevel &level, DinkyECS::Entity entity) {
+  if(level.world->has<SpriteEffect>(entity)) {
+    auto& se = level.world->get<SpriteEffect>(entity);
+
+    if(se.frames > 0) {
+      se.frames--;
+      return se.effect;
+    } else {
+      level.world->remove<SpriteEffect>(entity);
+      return nullptr;
+    }
+  } else {
+    return nullptr;
+  }
+}

systems.hpp

@@ -21,4 +21,7 @@ namespace System {
 
   void enemy_ai(GameLevel &level);
   void combat(GameLevel &level);
+
+  std::shared_ptr<sf::Shader> sprite_effect(GameLevel &level, DinkyECS::Entity entity);
+
 }