Improve performance

I profiled it and this was the slowest part.

1 files changed, 20 insertions, 15 deletions

diff --git a/src/main.rs b/src/main.rs
index 0e14863..0e40fdd 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -13,11 +13,11 @@ enum Result {
     Nothing,
 }
 
-struct Surfaces<'a> {
-    player: sdl2::surface::Surface<'a>,
-    enemy: sdl2::surface::Surface<'a>,
-    pbullet: sdl2::surface::Surface<'a>,
-    ebullet: sdl2::surface::Surface<'a>,
+struct Textures<'a> {
+    player: sdl2::render::Texture<'a>,
+    enemy: sdl2::render::Texture<'a>,
+    pbullet: sdl2::render::Texture<'a>,
+    ebullet: sdl2::render::Texture<'a>,
 }
 
 fn spawn(count: u64) -> Vec<state::Enemy> {
@@ -28,7 +28,7 @@ fn spawn(count: u64) -> Vec<state::Enemy> {
     }
 }
 
-fn frame(canvas: &mut sdl2::render::WindowCanvas, state: &mut state::State, events: &mut sdl2::event::EventPollIterator, surfaces: &Surfaces) -> Result {
+fn frame(canvas: &mut sdl2::render::WindowCanvas, state: &mut state::State, events: &mut sdl2::event::EventPollIterator, textures: &Textures) -> Result {
     let mut new_bullets = Vec::new();
     let count = state.count;
     for enemy in state.enemies.iter_mut() {
@@ -64,14 +64,14 @@ fn frame(canvas: &mut sdl2::render::WindowCanvas, state: &mut state::State, even
     state.bullets.append(&mut new_bullets);
     state.player_bullets.retain(|bullet| !state::PBullet::outside(bullet));
     for bullet in state.player_bullets.iter() {
-        bullet.draw(canvas, &surfaces.pbullet);
+        bullet.draw(canvas, &textures.pbullet);
     }
     for enemy in state.enemies.iter() {
-        enemy.draw(canvas, &surfaces.enemy);
+        enemy.draw(canvas, &textures.enemy);
     }
-    state.player.draw(canvas, &surfaces.player);
+    state.player.draw(canvas, &textures.player);
     for bullet in state.bullets.iter() {
-        bullet.draw(canvas, &surfaces.ebullet);
+        bullet.draw(canvas, &textures.ebullet);
     }
     state.count += 1;
     Result::Nothing
@@ -93,11 +93,16 @@ fn main() {
     let mut frame_count = 0;
     let mut state = state::State::new();
     let mut won = false;
-    let player_surface = sdl2::image::LoadSurface::from_file("assets/stallman.png").unwrap();
-    let enemy_surface = sdl2::image::LoadSurface::from_file("assets/gates.png").unwrap();
-    let ebullet_surface = sdl2::image::LoadSurface::from_file("assets/binary_blob.png").unwrap();
-    let pbullet_surface = sdl2::image::LoadSurface::from_file("assets/player_pepp.png").unwrap();
-    let surfaces = Surfaces { player: player_surface, enemy: enemy_surface, pbullet: pbullet_surface, ebullet: ebullet_surface };
+    let player_surface: sdl2::surface::Surface = sdl2::image::LoadSurface::from_file("assets/stallman.png").unwrap();
+    let enemy_surface: sdl2::surface::Surface = sdl2::image::LoadSurface::from_file("assets/gates.png").unwrap();
+    let ebullet_surface: sdl2::surface::Surface = sdl2::image::LoadSurface::from_file("assets/binary_blob.png").unwrap();
+    let pbullet_surface: sdl2::surface::Surface = sdl2::image::LoadSurface::from_file("assets/player_pepp.png").unwrap();
+    let texture_creator = canvas.texture_creator();
+    let player_texture = texture_creator.create_texture_from_surface(player_surface).unwrap();
+    let enemy_texture = texture_creator.create_texture_from_surface(enemy_surface).unwrap();
+    let ebullet_texture = texture_creator.create_texture_from_surface(ebullet_surface).unwrap();
+    let pbullet_texture = texture_creator.create_texture_from_surface(pbullet_surface).unwrap();
+    let surfaces = Textures { player: player_texture, enemy: enemy_texture, pbullet: pbullet_texture, ebullet: ebullet_texture };
     'running: loop {
         if won {
             for event in event_pump.poll_iter() {