feat(engine): add depth function to rendering::DrawProperties

2 files changed, 60 insertions, 3 deletions

diff --git a/engine/src/rendering.rs b/engine/src/rendering.rs
index dc3cb76..3af1ab8 100644
--- a/engine/src/rendering.rs
+++ b/engine/src/rendering.rs
@@ -321,6 +321,37 @@ impl Default for ScissorBox
     }
 }
 
+#[derive(Debug, Default, Clone, Copy, PartialEq, Eq)]
+pub enum DepthFunction
+{
+    /// Never passes.
+    Never,
+
+    /// Passes if the incoming depth value is less than the stored depth value.
+    #[default]
+    Less,
+
+    /// Passes if the incoming depth value is equal to the stored depth value.
+    Equal,
+
+    /// Passes if the incoming depth value is less than or equal to the stored depth
+    /// value.
+    LessOrEqual,
+
+    /// Passes if the incoming depth value is greater than the stored depth value.
+    Greater,
+
+    /// Passes if the incoming depth value is not equal to the stored depth value.
+    NotEqual,
+
+    /// Passes if the incoming depth value is greater than or equal to the stored depth
+    /// value.
+    GreaterOrEqual,
+
+    /// Always passes.
+    Always,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq)]
 #[non_exhaustive]
 pub struct DrawProperties
@@ -329,6 +360,7 @@ pub struct DrawProperties
     pub blending_enabled: bool,
     pub blending_config: BlendingConfig,
     pub depth_test_enabled: bool,
+    pub depth_function: DepthFunction,
     pub scissor_test_enabled: bool,
     pub scissor_box: ScissorBox,
     pub face_culling_enabled: bool,
@@ -343,6 +375,7 @@ impl Default for DrawProperties
             blending_enabled: false,
             blending_config: BlendingConfig::default(),
             depth_test_enabled: true,
+            depth_function: DepthFunction::default(),
             scissor_test_enabled: false,
             scissor_box: ScissorBox::default(),
             face_culling_enabled: false,
@@ -358,9 +391,10 @@ bitflags! {
         const BLENDING_CONFIG = 1 << 1;
         const BLENDING_ENABLED = 1 << 2;
         const DEPTH_TEST_ENABLED = 1 << 3;
-        const SCISSOR_TEST_ENABLED = 1 << 4;
-        const SCISSOR_BOX = 1 << 5;
-        const FACE_CULLING_ENABLED = 1 << 6;
+        const DEPTH_FUNCTION = 1 << 4;
+        const SCISSOR_TEST_ENABLED = 1 << 5;
+        const SCISSOR_BOX = 1 << 6;
+        const FACE_CULLING_ENABLED = 1 << 7;
     }
 }
 
diff --git a/engine/src/rendering/backend/opengl.rs b/engine/src/rendering/backend/opengl.rs
index dc636ef..49f857b 100644
--- a/engine/src/rendering/backend/opengl.rs
+++ b/engine/src/rendering/backend/opengl.rs
@@ -35,10 +35,12 @@ use opengl_bindings::misc::{
     define_scissor_box as gl_define_scissor_box,
     enable,
     get_viewport as gl_get_viewport,
+    set_depth_function as gl_set_depth_function,
     set_enabled,
     set_viewport as gl_set_viewport,
     BufferClearMask as GlBufferClearMask,
     Capability,
+    DepthFunction as GlDepthFunction,
 };
 use opengl_bindings::shader::{
     Error as GlShaderError,
@@ -108,6 +110,7 @@ use crate::rendering::{
     BufferClearMask,
     Command,
     CommandQueue,
+    DepthFunction,
     DrawMeshOptions,
     DrawPropertiesUpdateFlags,
     GraphicsProperties,
@@ -1033,6 +1036,26 @@ fn handle_commands(
                 }
 
                 if draw_props_update_flags
+                    .contains(DrawPropertiesUpdateFlags::DEPTH_FUNCTION)
+                {
+                    gl_set_depth_function(
+                        gl_context,
+                        match draw_props.depth_function {
+                            DepthFunction::Never => GlDepthFunction::Never,
+                            DepthFunction::Less => GlDepthFunction::Less,
+                            DepthFunction::Equal => GlDepthFunction::Equal,
+                            DepthFunction::LessOrEqual => GlDepthFunction::LessOrEqual,
+                            DepthFunction::Greater => GlDepthFunction::Greater,
+                            DepthFunction::NotEqual => GlDepthFunction::NotEqual,
+                            DepthFunction::GreaterOrEqual => {
+                                GlDepthFunction::GreaterOrEqual
+                            }
+                            DepthFunction::Always => GlDepthFunction::Always,
+                        },
+                    );
+                }
+
+                if draw_props_update_flags
                     .contains(DrawPropertiesUpdateFlags::SCISSOR_TEST_ENABLED)
                 {
                     set_enabled(