From 4930e7e8b2996ff6afb4b0a54390cdf9a354762d Mon Sep 17 00:00:00 2001
From: Victor Brekenfeld <github@drakulix.de>
Date: Fri, 12 Jun 2020 21:20:47 +0200
Subject: [PATCH] anvil: create a texture per backend

---
 anvil/src/glium_drawer.rs | 15 ++++++++++-----
 anvil/src/shell.rs        |  5 +++--
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/anvil/src/glium_drawer.rs b/anvil/src/glium_drawer.rs
index 8e67afe..9f436a8 100644
--- a/anvil/src/glium_drawer.rs
+++ b/anvil/src/glium_drawer.rs
@@ -1,6 +1,7 @@
 use std::{
     cell::{Ref, RefCell},
     rc::Rc,
+    sync::atomic::{AtomicUsize, Ordering},
 };
 
 use glium::{
@@ -38,6 +39,8 @@ use smithay::{
 use crate::shaders;
 use crate::shell::{MyCompositorToken, MyWindowMap, SurfaceData};
 
+pub static BACKEND_COUNTER: AtomicUsize = AtomicUsize::new(0);
+
 #[derive(Copy, Clone)]
 struct Vertex {
     position: [f32; 2],
@@ -52,6 +55,7 @@ mod implement_vertex {
 }
 
 pub struct GliumDrawer<F: GLGraphicsBackend + 'static> {
+    id: usize,
     display: GliumGraphicsBackend<F>,
     vertex_buffer: glium::VertexBuffer<Vertex>,
     index_buffer: glium::IndexBuffer<u16>,
@@ -107,6 +111,7 @@ impl<T: Into<GliumGraphicsBackend<T>> + GLGraphicsBackend + 'static> GliumDrawer
         let programs = opengl_programs!(&display);
 
         GliumDrawer {
+            id: BACKEND_COUNTER.fetch_add(1, Ordering::AcqRel),
             display,
             vertex_buffer,
             index_buffer,
@@ -151,6 +156,7 @@ impl<T: Into<GliumGraphicsBackend<T>> + GLGraphicsBackend + 'static> GliumDrawer
         let programs = opengl_programs!(&display);
 
         GliumDrawer {
+            id: BACKEND_COUNTER.fetch_add(1, Ordering::AcqRel),
             display,
             vertex_buffer,
             index_buffer,
@@ -321,7 +327,7 @@ impl<F: GLGraphicsBackend + 'static> GliumDrawer<F> {
                 // Pull a new buffer if available
                 if let Some(data) = attributes.user_data.get::<RefCell<SurfaceData>>() {
                     let mut data = data.borrow_mut();
-                    if data.texture.is_none() {
+                    if !data.texture.contains_key(&self.id) {
                         if let Some(buffer) = data.current_state.buffer.take() {
                             if let Ok(m) = self.texture_from_buffer(buffer.clone()) {
                                 // release the buffer if it was an SHM buffer
@@ -335,8 +341,7 @@ impl<F: GLGraphicsBackend + 'static> GliumDrawer<F> {
                                 {
                                     buffer.release();
                                 }
-
-                                data.texture = Some(m);
+                                data.texture.insert(self.id, m);
                             } else {
                                 // there was an error reading the buffer, release it, we
                                 // already logged the error
@@ -345,7 +350,7 @@ impl<F: GLGraphicsBackend + 'static> GliumDrawer<F> {
                         }
                     }
                     // Now, should we be drawn ?
-                    if data.texture.is_some() {
+                    if data.texture.contains_key(&self.id) {
                         // if yes, also process the children
                         if Role::<SubsurfaceRole>::has(role) {
                             x += data.current_state.sub_location.0;
@@ -364,7 +369,7 @@ impl<F: GLGraphicsBackend + 'static> GliumDrawer<F> {
             |_surface, attributes, role, &(mut x, mut y)| {
                 if let Some(ref data) = attributes.user_data.get::<RefCell<SurfaceData>>() {
                     let data = data.borrow();
-                    if let Some(ref metadata) = data.texture {
+                    if let Some(ref metadata) = data.texture.get(&self.id) {
                         // we need to re-extract the subsurface offset, as the previous closure
                         // only passes it to our children
                         if Role::<SubsurfaceRole>::has(role) {
diff --git a/anvil/src/shell.rs b/anvil/src/shell.rs
index d960393..a239c97 100644
--- a/anvil/src/shell.rs
+++ b/anvil/src/shell.rs
@@ -1,5 +1,6 @@
 use std::{
     cell::RefCell,
+    collections::HashMap,
     rc::Rc,
     sync::{Arc, Mutex},
 };
@@ -654,7 +655,7 @@ pub struct CommitedState {
 
 #[derive(Default)]
 pub struct SurfaceData {
-    pub texture: Option<crate::glium_drawer::TextureMetadata>,
+    pub texture: HashMap<usize, crate::glium_drawer::TextureMetadata>,
     pub geometry: Option<Rectangle>,
     pub resize_state: ResizeState,
     /// Minimum width and height, as requested by the surface.
@@ -673,7 +674,7 @@ impl SurfaceData {
     /// Apply a next state into the surface current state
     pub fn apply_state(&mut self, next_state: CommitedState) {
         if Self::merge_state(&mut self.current_state, next_state) {
-            self.texture = None;
+            self.texture.clear();
         }
     }