From b1883d5d48588321999d0aa896bcd9cf03792a83 Mon Sep 17 00:00:00 2001
From: triangle drawer <48007646+t18b219k@users.noreply.github.com>
Date: Sat, 13 Mar 2021 20:41:51 +0900
Subject: [PATCH] Add functions to register textures in egui_web and egui_glium
 (#226)

* add texture registering function

* fmt

* Revert "add texture registering function"

This reverts commit f9b4db12

* make get_texture public to get render target owned by Painter .

* revert egui_web painter.rs change
---
 egui_glium/src/painter.rs | 20 ++++++++++++++++++--
 egui_web/src/webgl1.rs    | 15 ++++++++++++---
 egui_web/src/webgl2.rs    | 14 ++++++++++++--
 3 files changed, 42 insertions(+), 7 deletions(-)

diff --git a/egui_glium/src/painter.rs b/egui_glium/src/painter.rs
index cb254183..b6876cb1 100644
--- a/egui_glium/src/painter.rs
+++ b/egui_glium/src/painter.rs
@@ -250,7 +250,23 @@ impl Painter {
         self.user_textures.push(Some(Default::default()));
         id
     }
-
+    /// register glium texture as egui texture
+    /// Usable for render to image rectangle
+    pub fn register_glium_texture(
+        &mut self,
+        texture: glium::texture::SrgbTexture2d,
+    ) -> egui::TextureId {
+        let id = self.alloc_user_texture();
+        if let egui::TextureId::User(id) = id {
+            if let Some(Some(user_texture)) = self.user_textures.get_mut(id as usize) {
+                *user_texture = UserTexture {
+                    pixels: vec![],
+                    gl_texture: Some(texture),
+                }
+            }
+        }
+        id
+    }
     pub fn set_user_texture(
         &mut self,
         id: egui::TextureId,
@@ -283,7 +299,7 @@ impl Painter {
         }
     }
 
-    fn get_texture(&self, texture_id: egui::TextureId) -> Option<&SrgbTexture2d> {
+    pub fn get_texture(&self, texture_id: egui::TextureId) -> Option<&SrgbTexture2d> {
         match texture_id {
             egui::TextureId::Egui => self.egui_texture.as_ref(),
             egui::TextureId::User(id) => self
diff --git a/egui_web/src/webgl1.rs b/egui_web/src/webgl1.rs
index 855d5bec..994bacf2 100644
--- a/egui_web/src/webgl1.rs
+++ b/egui_web/src/webgl1.rs
@@ -136,8 +136,7 @@ impl WebGlPainter {
             }
         }
     }
-
-    fn get_texture(&self, texture_id: egui::TextureId) -> Option<&WebGlTexture> {
+    pub fn get_texture(&self, texture_id: egui::TextureId) -> Option<&WebGlTexture> {
         match texture_id {
             egui::TextureId::Egui => Some(&self.egui_texture),
             egui::TextureId::User(id) => self
@@ -190,7 +189,17 @@ impl WebGlPainter {
             }
         }
     }
-
+    pub fn register_webgl_texture(&mut self, texture: WebGlTexture) -> egui::TextureId {
+        let id = self.alloc_user_texture_index();
+        if let Some(Some(user_texture)) = self.user_textures.get_mut(id) {
+            *user_texture = UserTexture {
+                size: (0, 0),
+                pixels: vec![],
+                gl_texture: Some(texture),
+            }
+        }
+        egui::TextureId::User(id as u64)
+    }
     fn paint_mesh(&self, mesh: &egui::epaint::Mesh16) -> Result<(), JsValue> {
         debug_assert!(mesh.is_valid());
 
diff --git a/egui_web/src/webgl2.rs b/egui_web/src/webgl2.rs
index 7e741be4..f0457c5c 100644
--- a/egui_web/src/webgl2.rs
+++ b/egui_web/src/webgl2.rs
@@ -139,7 +139,7 @@ impl WebGl2Painter {
         }
     }
 
-    fn get_texture(&self, texture_id: egui::TextureId) -> Option<&WebGlTexture> {
+    pub fn get_texture(&self, texture_id: egui::TextureId) -> Option<&WebGlTexture> {
         match texture_id {
             egui::TextureId::Egui => Some(&self.egui_texture),
             egui::TextureId::User(id) => self
@@ -192,7 +192,17 @@ impl WebGl2Painter {
             }
         }
     }
-
+    pub fn register_webgl_texture(&mut self, texture: WebGlTexture) -> egui::TextureId {
+        let id = self.alloc_user_texture_index();
+        if let Some(Some(user_texture)) = self.user_textures.get_mut(id) {
+            *user_texture = UserTexture {
+                size: (0, 0),
+                pixels: vec![],
+                gl_texture: Some(texture),
+            }
+        }
+        egui::TextureId::User(id as u64)
+    }
     fn paint_mesh(&self, mesh: &egui::epaint::Mesh16) -> Result<(), JsValue> {
         debug_assert!(mesh.is_valid());