Switch to lightmap texture based lighting

shaders/lighting.glsl

@@ -1,46 +0,0 @@
-// Based on https://github.com/romrz/Basic-2D-lighting
-
-uniform sampler2D texture;
-uniform vec2 resolution;
-uniform vec2 mouse;
-uniform float time;
-uniform bool has_texture;
-
-// The RGB values are the ambient light color
-// and the alpha is the ambient intensity
-uniform vec4 ambientData;
-// The RGB values are the light color
-// and the alpha is the light intensity
-uniform vec4 lightData;
-// Maximum radius of the light
-uniform float lightSize;
-
-void main() {
-  // Light's position
-  vec2 position = mouse/resolution.xx;
-
-  // Makes the light change its size slightly to make a fire effect
-  float maxDistance = lightSize + 0.015*sin(time);
-  // Gets the distance from the light's position and the fragment coord
-  float distance = distance(gl_FragCoord.xy/resolution.xx, position);
-  // Calculates the amount of light for the fragment
-  float value = 1.0 - smoothstep(-0.2, maxDistance, distance);
-
-  // Gets the original color from the texture
-  vec4 pixel = texture2D(texture, gl_TexCoord[0].xy);
-  if (!has_texture) {
-    pixel = gl_Color;
-  }
-
-  // Applies the ambient light to the original pixel color
-  vec3 ambient = pixel.rgb * ambientData.rgb * ambientData.a;
-
-  // Calculates the light color for the pixel
-  vec3 light = lightData.rgb * lightData.a * clamp(value, 0.0, 1.0);
-
-  // Applies the light to the pixel
-  vec3 intensity = ambient + light;
-  vec4 final = pixel * vec4(intensity.r, intensity.g, intensity.b, 1.0);
-
-  gl_FragColor = final;
-}

src/app.rs

@@ -7,7 +7,8 @@ use gamedebug_core::{imm, imm_dbg};
 use sfml::{
     audio::SoundSource,
     graphics::{
-        Color, Rect, RenderTarget, RenderTexture, RenderWindow, Sprite, Transformable, View,
+        BlendMode, Color, Rect, RenderStates, RenderTarget, RenderTexture, RenderWindow, Sprite,
+        Transformable, View,
     },
     system::Vector2u,
     window::{Event, Key},
@@ -15,7 +16,7 @@ use sfml::{
 
 use crate::{
     debug::DebugState,
-    game::{for_each_tile_on_screen, Biome, GameState},
+    game::{for_each_tile_on_screen, Biome, GameState, LightSource},
     graphics::{self, ScreenPos, ScreenPosScalar},
     input::Input,
     math::{center_offset, px_per_frame_to_km_h, WorldPos, M_PER_PX, TILE_SIZE},
@@ -36,6 +37,8 @@ pub struct App {
     pub scale: u8,
     /// RenderTexture for rendering the game at its native resolution
     pub rt: RenderTexture,
+    /// Light map overlay, blended together with the non-lighted version of the scene
+    pub light_map: RenderTexture,
 }
 
 impl App {
@@ -49,6 +52,8 @@ impl App {
         let rw_size = rw.size();
         let rt =
             RenderTexture::new(rw_size.x, rw_size.y).context("Failed to create render texture")?;
+        let light_map = RenderTexture::new(rw_size.x, rw_size.y)
+            .context("Failed to create lightmap texture")?;
         Ok(Self {
             rw,
             should_quit: false,
@@ -59,6 +64,7 @@ impl App {
             debug: DebugState::default(),
             scale: 1,
             rt,
+            light_map,
         })
     }
 
@@ -198,6 +204,8 @@ impl App {
             } else {
                 t.bg = self.game.tile_to_place;
             }
+        } else if self.input.mid_pressed {
+            self.game.light_sources.push(LightSource { pos: wpos });
         }
         if self.game.camera_offset.y > 643_000 {
             self.game.current_biome = Biome::Underground;
@@ -244,10 +252,10 @@ impl App {
     }
 
     fn do_rendering(&mut self) {
+        self.game.light_pass(&mut self.light_map, &self.res);
         self.rt.clear(Color::rgb(55, 221, 231));
-        self.game.render_pre_step(&mut self.res, self.rt.size());
         self.game.draw_world(&mut self.rt, &mut self.res);
-        self.game.draw_entities(&mut self.rt, &mut self.res);
+        self.game.draw_entities(&mut self.rt);
         self.rt.display();
         let mut spr = Sprite::with_texture(self.rt.texture());
         spr.set_scale((self.scale as f32, self.scale as f32));
@@ -255,6 +263,12 @@ impl App {
         spr.set_position((vco.x as f32, vco.y as f32));
         self.rw.clear(Color::rgb(40, 10, 70));
         self.rw.draw(&spr);
+        // Draw light overlay with multiply blending
+        let mut rst = RenderStates::default();
+        rst.blend_mode = BlendMode::MULTIPLY;
+        self.light_map.display();
+        spr.set_texture(self.light_map.texture(), false);
+        self.rw.draw_with_renderstates(&spr, &rst);
         self.sf_egui
             .do_frame(|ctx| {
                 if self.debug.panel {

src/game.rs

@@ -1,12 +1,10 @@
 mod player;
 
 use derivative::Derivative;
-use egui_inspect::{derive::Inspect, inspect};
+use egui_inspect::derive::Inspect;
 use sfml::{
     graphics::{
-        glsl::{Vec2, Vec4},
-        Color, Rect, RectangleShape, RenderStates, RenderTarget, RenderTexture, Shape, Sprite,
-        Transformable,
+        Color, Rect, RectangleShape, RenderTarget, RenderTexture, Shape, Sprite, Transformable,
     },
     system::{Clock, Vector2u},
     SfBox,
@@ -38,7 +36,12 @@ pub struct GameState {
     pub ambient_light: f32,
     #[opaque]
     pub clock: SfBox<Clock>,
-    lighting_params: LightingData,
+    pub light_sources: Vec<LightSource>,
+}
+
+#[derive(Debug, Inspect)]
+pub struct LightSource {
+    pub pos: WorldPos,
 }
 
 #[derive(PartialEq, Eq, Clone, Copy, Debug, Inspect)]
@@ -48,32 +51,26 @@ pub enum Biome {
 }
 
 impl GameState {
-    pub(crate) fn draw_world(&mut self, rw: &mut RenderTexture, res: &mut Res) {
-        let mut rs = RenderStates::default();
-        res.lighting_shader.set_uniform_bool("has_texture", true);
-        rs.set_shader(Some(&res.lighting_shader));
+    pub(crate) fn draw_world(&mut self, rt: &mut RenderTexture, res: &mut Res) {
         let mut s = Sprite::with_texture(&res.tile_atlas);
-        for_each_tile_on_screen(self.camera_offset, rw.size(), |tp, sp| {
+        for_each_tile_on_screen(self.camera_offset, rt.size(), |tp, sp| {
             let tile = self.world.tile_at_mut(tp, &self.worldgen);
             s.set_position(sp.to_sf_vec());
             if tile.bg != Tile::EMPTY {
                 s.set_texture_rect(Rect::new((tile.bg - 1) as i32 * 32, 0, 32, 32));
-                rw.draw_with_renderstates(&s, &rs);
+                rt.draw(&s);
             }
             if tile.mid != Tile::EMPTY {
                 s.set_texture_rect(Rect::new((tile.mid - 1) as i32 * 32, 0, 32, 32));
-                rw.draw_with_renderstates(&s, &rs);
+                rt.draw(&s);
             }
             if tile.fg != Tile::EMPTY {
                 s.set_texture_rect(Rect::new((tile.fg - 1) as i32 * 32, 0, 32, 32));
-                rw.draw_with_renderstates(&s, &rs);
+                rt.draw(&s);
             }
         });
     }
-    pub fn draw_entities(&mut self, rw: &mut RenderTexture, res: &mut Res) {
-        let mut rend_st = RenderStates::default();
-        res.lighting_shader.set_uniform_bool("has_texture", false);
-        rend_st.set_shader(Some(&res.lighting_shader));
+    pub fn draw_entities(&mut self, rw: &mut RenderTexture) {
         let (x, y, w, h) = self.player.col_en.en.xywh();
         let mut rect_sh = RectangleShape::new();
         rect_sh.set_position((
@@ -81,7 +78,7 @@ impl GameState {
             (y - self.camera_offset.y as i32) as f32,
         ));
         rect_sh.set_size((w as f32, h as f32));
-        rw.draw_with_renderstates(&rect_sh, &rend_st);
+        rw.draw(&rect_sh);
         rect_sh.set_size((2., 2.));
         rect_sh.set_fill_color(Color::RED);
         rect_sh.set_position((
@@ -90,56 +87,21 @@ impl GameState {
         ));
         rw.draw(&rect_sh);
     }
-    pub fn render_pre_step(&mut self, res: &mut Res, rt_size: Vector2u) {
-        res.lighting_shader.set_uniform_current_texture("texture");
-        res.lighting_shader
-            .set_uniform_float("time", self.clock.elapsed_time().as_seconds() * 10.0);
-        res.lighting_shader.set_uniform_vec2(
-            "mouse",
-            Vec2::new(rt_size.x as f32 / 2.0, rt_size.y as f32 / 2.0),
-        );
-        res.lighting_shader
-            .set_uniform_vec2("resolution", Vec2::new(rt_size.x as f32, rt_size.y as f32));
-        res.lighting_shader
-            .set_uniform_vec4("lightData", self.lighting_params.light);
-        res.lighting_shader
-            .set_uniform_vec4("ambientData", self.lighting_params.ambient);
-        res.lighting_shader
-            .set_uniform_float("lightSize", self.lighting_params.size);
-    }
-}
 
-#[derive(Debug, Inspect)]
-struct LightingData {
-    #[inspect_with(inspect_vec4)]
-    light: Vec4,
-    #[inspect_with(inspect_vec4)]
-    ambient: Vec4,
-    size: f32,
-}
-
-fn inspect_vec4(val: &mut Vec4, ui: &mut egui::Ui, _id: u64) {
-    inspect! {
-        ui, val.x, val.y, val.z, val.w
-    }
-}
-
-impl Default for LightingData {
-    fn default() -> Self {
-        Self {
-            light: Vec4 {
-                x: 1.0,
-                y: 0.8,
-                z: 0.2,
-                w: 2.0,
-            },
-            ambient: Vec4 {
-                x: 0.3,
-                y: 0.3,
-                z: 0.8,
-                w: 0.3,
-            },
-            size: 0.3,
+    pub(crate) fn light_pass(&mut self, lightmap: &mut RenderTexture, res: &Res) {
+        // Clear light map
+        // You can clear to a brighter color to increase ambient light level
+        lightmap.clear(Color::rgba(0, 0, 0, 255));
+        for ls in &self.light_sources {
+            let (x, y) = (
+                ls.pos.x as i32 - self.camera_offset.x as i32,
+                ls.pos.y as i32 - self.camera_offset.y as i32,
+            );
+            let mut s = Sprite::with_texture(&res.light_texture);
+            s.set_scale((3.0, 3.0));
+            s.set_origin((32., 32.));
+            s.set_position((x as f32, y as f32));
+            lightmap.draw(&s);
         }
     }
 }
@@ -180,7 +142,7 @@ impl Default for GameState {
             worldgen: Worldgen::default(),
             ambient_light: 1.0,
             clock: Clock::start(),
-            lighting_params: Default::default(),
+            light_sources: Vec::new(),
         }
     }
 }

src/input.rs

@@ -10,6 +10,7 @@ pub struct Input {
     pub lmb_down: bool,
     pub rmb_down: bool,
     pub mouse_down_loc: ScreenPos,
+    pub mid_pressed: bool,
 }
 
 impl Input {
@@ -33,6 +34,9 @@ impl Input {
                 if button == mouse::Button::Right {
                     self.rmb_down = true;
                 }
+                if button == mouse::Button::Middle {
+                    self.mid_pressed = true;
+                }
             }
             &Event::MouseButtonReleased { button, .. } => {
                 if button == mouse::Button::Left {
@@ -51,6 +55,7 @@ impl Input {
     }
     /// Pressed event should be cleared every frame
     pub fn clear_pressed(&mut self) {
+        self.mid_pressed = false;
         self.pressed.clear();
     }
     pub fn down(&self, key: Key) -> bool {

src/res.rs

@@ -1,27 +1,20 @@
-use sfml::{
-    audio::Music,
-    graphics::{Shader, ShaderType, Texture},
-    SfBox,
-};
+use sfml::{audio::Music, graphics::Texture, SfBox};
 
 #[derive(Debug)]
 pub struct Res {
     pub tile_atlas: SfBox<Texture>,
+    pub light_texture: SfBox<Texture>,
     pub surf_music: Music<'static>,
     pub und_music: Music<'static>,
-    pub lighting_shader: Shader<'static>,
 }
 
 impl Res {
     pub fn load() -> anyhow::Result<Self> {
         Ok(Self {
             tile_atlas: Texture::from_file("res/tiles.png")?,
+            light_texture: Texture::from_file("res/lightcircle.png")?,
             surf_music: Music::from_file("res/music.ogg").unwrap(),
             und_music: Music::from_file("res/cave2.ogg").unwrap(),
-            lighting_shader: Shader::from_memory(
-                include_str!("../shaders/lighting.glsl"),
-                ShaderType::Fragment,
-            )?,
         })
     }
 }