From ac3fedba0239632b350a252b74e520b42912e6e2 Mon Sep 17 00:00:00 2001
From: HampusM <hampus@hampusmat.com>
Date: Mon, 20 Apr 2026 17:28:23 +0200
Subject: feat(engine): move handling of viewport resizing to renderer module

---
 engine/src/renderer/opengl.rs | 120 +++++++++---------------------------------
 1 file changed, 25 insertions(+), 95 deletions(-)

(limited to 'engine/src/renderer')

diff --git a/engine/src/renderer/opengl.rs b/engine/src/renderer/opengl.rs
index 9ba1d3a..1cd46b2 100644
--- a/engine/src/renderer/opengl.rs
+++ b/engine/src/renderer/opengl.rs
@@ -5,8 +5,7 @@ use std::borrow::Cow;
 use std::collections::HashMap;
 
 use ecs::actions::Actions;
-use ecs::entity::obtainer::Obtainer as EntityObtainer;
-use ecs::event::component::{Changed, Removed};
+use ecs::event::component::Removed;
 use ecs::pair::{Pair, Wildcard};
 use ecs::query::term::Without;
 use ecs::sole::Single;
@@ -37,12 +36,12 @@ use opengl_bindings::debug::{
 use opengl_bindings::misc::{
     BufferClearMask as GlBufferClearMask,
     Capability,
-    SetViewportError as GlSetViewportError,
     clear_buffers,
     define_scissor_box as gl_define_scissor_box,
     enable,
     get_viewport as gl_get_viewport,
     set_enabled,
+    set_viewport as gl_set_viewport,
 };
 use opengl_bindings::shader::{
     Error as GlShaderError,
@@ -179,82 +178,11 @@ impl ecs::extension::Extension for Extension
         collector.add_system(*POST_RENDER_PHASE, prepare_windows);
         collector.add_system(*POST_RENDER_PHASE, init_window_graphics);
 
-        collector.add_observer(handle_window_changed);
+        collector.add_observer(super::handle_window_changed);
         collector.add_observer(handle_window_removed);
     }
 }
 
-#[tracing::instrument(skip_all)]
-fn handle_window_changed(
-    observe: Observe<Pair<Changed, Window>>,
-    entity_obtainer: EntityObtainer,
-)
-{
-    for evt_match in &observe {
-        let window_ent = evt_match.get_ent_infallible();
-
-        tracing::trace!(
-            new_state = ?evt_match.get_changed_comp(),
-            "Handling window change"
-        );
-
-        let Some(surface_spec) = window_ent.get::<SurfaceSpec>() else {
-            continue;
-        };
-
-        let Some(renderer_ctx_ent_id) = window_ent
-            .get_matching_components(
-                Pair::builder()
-                    .relation::<WindowUsingRendererCtx>()
-                    .target_id(Wildcard::uid())
-                    .build()
-                    .id(),
-            )
-            .next()
-            .map(|comp_ref| comp_ref.id().target_entity())
-        else {
-            continue;
-        };
-
-        let Some(renderer_ctx_ent) = entity_obtainer.get_entity(renderer_ctx_ent_id)
-        else {
-            tracing::error!("Renderer context entity does not exist");
-            continue;
-        };
-
-        let Some(graphics_context) = renderer_ctx_ent.get::<GraphicsContext>() else {
-            tracing::error!(
-                "Renderer context entity does not have a GraphicsContext component"
-            );
-            continue;
-        };
-
-        let Some(surface) = graphics_context.surfaces.get(&surface_spec.id) else {
-            tracing::error!(
-                window_entity_id = %window_ent.uid(),
-                "Surface specified by window entity's {} component does not exist",
-                type_name::<SurfaceSpec>()
-            );
-            continue;
-        };
-
-        let Ok(current_graphics_context) =
-            graphics_context.gl_context.make_current(surface)
-        else {
-            tracing::error!("Failed to make graphics context current");
-            continue;
-        };
-
-        if let Err(err) = set_viewport(
-            &current_graphics_context,
-            Vec2::default(),
-            evt_match.get_changed_comp().inner_size(),
-        ) {
-            tracing::error!("Failed to set viewport: {err}");
-        }
-    }
-}
-
 #[tracing::instrument(skip_all)]
 fn handle_window_removed(observe: Observe<Pair<Removed, Window>>, mut actions: Actions)
 {
@@ -488,9 +416,11 @@ fn init_window_graphics(
             continue;
         };
 
-        if let Err(err) =
-            set_viewport(&curr_gl_context, Vec2 { x: 0, y: 0 }, window.inner_size())
-        {
+        if let Err(err) = gl_set_viewport(
+            &curr_gl_context,
+            &Vec2 { x: 0, y: 0 }.into(),
+            &window.inner_size().clone().into(),
+        ) {
             tracing::error!("Failed to set viewport: {err}");
         }
 
@@ -1177,6 +1107,23 @@ fn handle_commands(
                         );
                     }
                 }
+                RendererCommand::SetViewport {
+                    size: viewport_size,
+                    position: viewport_position,
+                } => {
+                    let Some(curr_gl_ctx) = &opt_curr_gl_ctx else {
+                        tracing::error!("No GL context is current");
+                        continue;
+                    };
+
+                    if let Err(err) = gl_set_viewport(
+                        curr_gl_ctx,
+                        &viewport_position.into(),
+                        &viewport_size.into(),
+                    ) {
+                        tracing::error!("Failed to set viewport: {err}");
+                    }
+                }
             }
         }
     }
@@ -1244,23 +1191,6 @@ fn create_texture_object(
     Ok(())
 }
 
-fn set_viewport(
-    current_context: &CurrentContextWithFns<'_>,
-    position: Vec2<u32>,
-    size: &Dimens<u32>,
-) -> Result<(), GlSetViewportError>
-{
-    let position =
-        opengl_bindings::data_types::Vec2::<u32> { x: position.x, y: position.y };
-
-    let size = opengl_bindings::data_types::Dimens::<u32> {
-        width: size.width,
-        height: size.height,
-    };
-
-    opengl_bindings::misc::set_viewport(current_context, &position, &size)
-}
-
 fn draw_mesh(
     current_context: &CurrentContextWithFns<'_>,
     graphics_mesh: &GraphicsMesh,
-- 
cgit v1.2.3-18-g5258