From e669b499ef06ff0ace25ad0c06e6b8a8ac6dacce Mon Sep 17 00:00:00 2001
From: Tomasz Sterna <tomasz@sterna.link>
Date: Mon, 23 Aug 2021 19:20:01 +0200
Subject: [PATCH] Add support for DepthStencil texture format

---
 native/sapp-windows/src/gl.rs | 3 +++
 src/graphics.rs               | 5 ++++-
 src/graphics/texture.rs       | 8 ++++++++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/native/sapp-windows/src/gl.rs b/native/sapp-windows/src/gl.rs
index 9bdcb63b..937d4f93 100644
--- a/native/sapp-windows/src/gl.rs
+++ b/native/sapp-windows/src/gl.rs
@@ -89,6 +89,8 @@ pub const GL_FRAGMENT_SHADER: u32 = 0x8B30;
 pub const GL_FLOAT: u32 = 0x1406;
 pub const GL_TEXTURE_MAX_LOD: u32 = 0x813B;
 pub const GL_DEPTH_COMPONENT: u32 = 0x1902;
+pub const GL_DEPTH_STENCIL: u32 = 0x84F9;
+pub const GL_DEPTH24_STENCIL8: u32 = 0x88F0;
 pub const GL_ONE_MINUS_DST_ALPHA: u32 = 0x0305;
 pub const GL_COLOR: u32 = 0x1800;
 pub const GL_TEXTURE_2D_ARRAY: u32 = 0x8C1A;
@@ -130,6 +132,7 @@ pub const GL_INVERT: u32 = 0x150A;
 pub const GL_INT: u32 = 0x1404;
 pub const GL_UNSIGNED_INT: u32 = 0x1405;
 pub const GL_UNSIGNED_SHORT: u32 = 0x1403;
+pub const GL_UNSIGNED_INT_24_8: u32 = 0x84FA;
 pub const GL_NEAREST: u32 = 0x2600;
 pub const GL_SCISSOR_TEST: u32 = 0x0C11;
 pub const GL_LEQUAL: u32 = 0x0203;
diff --git a/src/graphics.rs b/src/graphics.rs
index 60464f9c..28d08f74 100644
--- a/src/graphics.rs
+++ b/src/graphics.rs
@@ -584,7 +584,10 @@ impl RenderPass {
             if let Some(depth_img) = depth_img {
                 glFramebufferTexture2D(
                     GL_FRAMEBUFFER,
-                    GL_DEPTH_ATTACHMENT,
+                    match depth_img.format {
+                        TextureFormat::DepthStencil => GL_DEPTH_ATTACHMENT | GL_STENCIL_ATTACHMENT,
+                        _ => GL_DEPTH_ATTACHMENT,
+                    },
                     GL_TEXTURE_2D,
                     depth_img.texture,
                     0,
diff --git a/src/graphics/texture.rs b/src/graphics/texture.rs
index 1bcc5c46..7fa71837 100644
--- a/src/graphics/texture.rs
+++ b/src/graphics/texture.rs
@@ -54,6 +54,7 @@ pub enum TextureFormat {
     RGBA8,
     Depth,
     Alpha,
+    DepthStencil,
 }
 
 /// Converts from TextureFormat to (internal_format, format, pixel_type)
@@ -67,6 +68,9 @@ impl From<TextureFormat> for (GLenum, GLenum, GLenum) {
             TextureFormat::Alpha => (GL_ALPHA, GL_ALPHA, GL_UNSIGNED_BYTE),
             #[cfg(not(target_arch = "wasm32"))]
             TextureFormat::Alpha => (GL_R8, GL_RED, GL_UNSIGNED_BYTE), // texture updates will swizzle Red -> Alpha to match WASM
+            TextureFormat::DepthStencil => {
+                (GL_DEPTH24_STENCIL8, GL_DEPTH_STENCIL, GL_UNSIGNED_INT_24_8)
+            }
         }
     }
 }
@@ -80,6 +84,7 @@ impl TextureFormat {
             TextureFormat::RGBA8 => 4 * square,
             TextureFormat::Depth => 2 * square,
             TextureFormat::Alpha => 1 * square,
+            TextureFormat::DepthStencil => 4 * square,
         }
     }
 }
@@ -148,6 +153,9 @@ impl Texture {
                 bytes_data.len()
             );
         }
+        if params.format == TextureFormat::DepthStencil {
+            assert_eq!(params.filter, FilterMode::Nearest);
+        }
 
         let (internal_format, format, pixel_type) = params.format.into();