Split the software renderer in its own crate: i-slint-renderer-software (#10229)

The goal is to be able to enable feature conditionally with `i-slint-renderer-software/?...`

NOTE: this change the implementation of
`SceneBuilder::platform_text_fill_brush/platform_text_stroke_brush`
It was warning about `non_exhaustive_omitted_patterns`.
And it changed it to always return the brush color so gradient gets
converted to plain color instead of None.
This is the behavior with the non-parley renderer

api/cpp/Cargo.toml

@@ -41,14 +41,19 @@ renderer-femtovg-wgpu = ["i-slint-backend-selector/renderer-femtovg-wgpu"]
 renderer-skia = ["i-slint-backend-selector/renderer-skia", "i-slint-renderer-skia", "raw-window-handle"]
 renderer-skia-opengl = ["i-slint-backend-selector/renderer-skia-opengl", "renderer-skia"]
 renderer-skia-vulkan = ["i-slint-backend-selector/renderer-skia-vulkan", "renderer-skia"]
-renderer-software = ["i-slint-backend-selector/renderer-software"]
+renderer-software = ["i-slint-backend-selector/renderer-software", "dep:i-slint-renderer-software"]
 gettext = ["i-slint-core/gettext-rs"]
 accessibility = ["i-slint-backend-selector/accessibility"]
 system-testing = ["i-slint-backend-selector/system-testing"]
 
-std = ["i-slint-core/default", "i-slint-core/image-default-formats", "i-slint-backend-selector"]
+std = [
+  "i-slint-core/default",
+  "i-slint-core/image-default-formats",
+  "i-slint-backend-selector",
+  "i-slint-renderer-software?/std",
+]
 freestanding = ["i-slint-core/libm", "i-slint-core/unsafe-single-threaded"]
-experimental = ["i-slint-core/experimental"]
+experimental = ["i-slint-renderer-software?/experimental"]
 
 default = ["std", "backend-winit", "renderer-femtovg", "backend-qt"]
 
@@ -56,6 +61,7 @@ default = ["std", "backend-winit", "renderer-femtovg", "backend-qt"]
 i-slint-backend-selector = { workspace = true, optional = true }
 i-slint-backend-testing = { workspace = true, optional = true, features = ["ffi"] }
 i-slint-renderer-skia = { workspace = true, features = ["default", "x11", "wayland"], optional = true }
+i-slint-renderer-software = { workspace = true, optional = true }
 i-slint-core = { workspace = true, features = ["ffi"] }
 slint-interpreter = { workspace = true, features = ["ffi", "compat-1-2"], optional = true }
 raw-window-handle = { version = "0.6", optional = true }

api/cpp/cbindgen.rs

@@ -341,7 +341,6 @@ fn gen_corelib(
         "Rect",
         "SortOrder",
         "BitmapFont",
-        "PhysicalRegion",
     ]
     .iter()
     .chain(items.iter())
@@ -496,10 +495,12 @@ fn gen_corelib(
                 "SharedPixelBuffer",
                 "SharedImageBuffer",
                 "StaticTextures",
-                "BorrowedOpenGLTextureOrigin"
+                "BorrowedOpenGLTextureOrigin",
+                "PhysicalRegion",
+                "PHYSICAL_REGION_MAX_SIZE",
             ],
             "slint_image_internal.h",
-            "#include \"slint_color.h\"\nnamespace slint::cbindgen_private { struct ParsedSVG{}; struct HTMLImage{}; using namespace vtable; namespace types{ struct NineSliceImage{}; } }",
+            "#include \"slint_color.h\"\nnamespace slint::cbindgen_private { struct ParsedSVG{}; struct HTMLImage{}; struct PhysicalPx; using namespace vtable; namespace types{ struct NineSliceImage{}; } }",
         ),
         (
             vec!["Color", "slint_color_brighter", "slint_color_darker",
@@ -582,6 +583,7 @@ fn gen_corelib(
             "ConicGradientBrush",
             "slint_conic_gradient_normalize_stops",
             "slint_conic_gradient_apply_rotation",
+            "PHYSICAL_REGION_MAX_SIZE",
         ]
         .into_iter()
         .chain(config.export.exclude.iter().map(|s| s.as_str()))
@@ -622,6 +624,7 @@ fn gen_corelib(
             .with_src(crate_dir.join("input.rs"))
             .with_src(crate_dir.join("item_rendering.rs"))
             .with_src(crate_dir.join("window.rs"))
+            .with_src(crate_dir.join("../renderers/software/lib.rs"))
             .with_include("slint_enums_internal.h")
             .generate()
             .with_context(|| format!("Unable to generate bindings for {internal_header}"))?
@@ -881,6 +884,7 @@ namespace slint::cbindgen_private {
     using slint::cbindgen_private::types::TexturePixelFormat;
     struct DrawTextureArgs;
     struct DrawRectangleArgs;
+    using types::PhysicalRegion;
 }
 ",
         )

api/cpp/include/slint-platform.h

@@ -602,7 +602,7 @@ public:
         auto rectangles() const
         {
             SharedVector<cbindgen_private::IntRect> rectangles;
-            slint_software_renderer_region_to_rects(&inner, &rectangles);
+            cbindgen_private::slint_software_renderer_region_to_rects(&inner, &rectangles);
 #    if __cpp_lib_ranges >= 202110L // DR20 P2415R2
             using std::ranges::owning_view;
 #    else

api/cpp/platform.rs

@@ -359,12 +359,12 @@ mod software_renderer {
     type SoftwareRendererOpaque = *const c_void;
     use i_slint_core::SharedVector;
     use i_slint_core::graphics::{IntRect, Rgb8Pixel};
-    use i_slint_core::software_renderer::{
+    use i_slint_renderer_software::{
         PhysicalRegion, RepaintBufferType, Rgb565Pixel, SoftwareRenderer,
     };
 
     #[cfg(feature = "experimental")]
-    use i_slint_core::software_renderer::{TargetPixelBuffer, TexturePixelFormat};
+    use i_slint_renderer_software::{TargetPixelBuffer, TexturePixelFormat};
 
     #[cfg(feature = "experimental")]
     type CppTargetPixelBufferUserData = *mut c_void;
@@ -398,8 +398,8 @@ mod software_renderer {
         pub tiling_gap_y: u32,
     }
     #[cfg(feature = "experimental")]
-    impl From<&i_slint_core::software_renderer::DrawTextureArgs> for DrawTextureArgs {
-        fn from(from: &i_slint_core::software_renderer::DrawTextureArgs) -> Self {
+    impl From<&i_slint_renderer_software::DrawTextureArgs> for DrawTextureArgs {
+        fn from(from: &i_slint_renderer_software::DrawTextureArgs) -> Self {
             let source = from.source();
             Self {
                 image_data: source.data.as_ptr(),
@@ -448,8 +448,8 @@ mod software_renderer {
         pub rotation: i32,
     }
     #[cfg(feature = "experimental")]
-    impl From<&i_slint_core::software_renderer::DrawRectangleArgs> for DrawRectangleArgs {
-        fn from(from: &i_slint_core::software_renderer::DrawRectangleArgs) -> Self {
+    impl From<&i_slint_renderer_software::DrawRectangleArgs> for DrawRectangleArgs {
+        fn from(from: &i_slint_renderer_software::DrawRectangleArgs) -> Self {
             Self {
                 x: from.x,
                 y: from.y,
@@ -494,7 +494,7 @@ mod software_renderer {
     }
 
     #[cfg(feature = "experimental")]
-    impl<TargetPixel: i_slint_core::software_renderer::TargetPixel> TargetPixelBuffer
+    impl<TargetPixel: i_slint_renderer_software::TargetPixel> TargetPixelBuffer
         for CppTargetPixelBuffer<TargetPixel>
     {
         type TargetPixel = TargetPixel;
@@ -524,7 +524,7 @@ mod software_renderer {
         /// Draw a rectangle specified by the DrawRectangleArgs. That rectangle must be clipped to the given region
         fn draw_rectangle(
             &mut self,
-            args: &i_slint_core::software_renderer::DrawRectangleArgs,
+            args: &i_slint_renderer_software::DrawRectangleArgs,
             clip: &PhysicalRegion,
         ) -> bool {
             let args = args.into();
@@ -533,7 +533,7 @@ mod software_renderer {
 
         fn draw_texture(
             &mut self,
-            texture: &i_slint_core::software_renderer::DrawTextureArgs,
+            texture: &i_slint_renderer_software::DrawTextureArgs,
             clip: &PhysicalRegion,
         ) -> bool {
             let texture = texture.into();
@@ -620,8 +620,8 @@ mod software_renderer {
         user_data: *mut core::ffi::c_void,
     }
 
-    impl<TargetPixel: i_slint_core::software_renderer::TargetPixel>
-        i_slint_core::software_renderer::LineBufferProvider for LineByLineProcessor<TargetPixel>
+    impl<TargetPixel: i_slint_renderer_software::TargetPixel>
+        i_slint_renderer_software::LineBufferProvider for LineByLineProcessor<TargetPixel>
     {
         type TargetPixel = TargetPixel;
         fn process_line(
@@ -710,7 +710,7 @@ mod software_renderer {
         r: SoftwareRendererOpaque,
         rotation: i32,
     ) {
-        use i_slint_core::software_renderer::RenderingRotation;
+        use i_slint_renderer_software::RenderingRotation;
         let renderer = unsafe { &*(r as *const SoftwareRenderer) };
         renderer.set_rendering_rotation(match rotation {
             90 => RenderingRotation::Rotate90,