WIP: Working clip rects for glium

emigui/src/math.rs

@@ -63,6 +63,10 @@ impl Vec2 {
         vec2(self.x.ceil(), self.y.ceil())
     }
 
+    pub fn is_finite(&self) -> bool {
+        self.x.is_finite() && self.y.is_finite()
+    }
+
     pub fn min(self, other: Vec2) -> Self {
         vec2(self.x.min(other.x), self.y.min(other.y))
     }
@@ -195,6 +199,10 @@ impl Pos2 {
     pub fn ceil(self) -> Self {
         pos2(self.x.ceil(), self.y.ceil())
     }
+
+    pub fn is_finite(&self) -> bool {
+        self.x.is_finite() && self.y.is_finite()
+    }
 }
 
 impl std::ops::AddAssign<Vec2> for Pos2 {
@@ -342,6 +350,14 @@ impl Rect {
         self.max.y - self.min.y
     }
 
+    pub fn is_empty(&self) -> bool {
+        self.max.x < self.min.x || self.max.y < self.min.y
+    }
+
+    pub fn is_finite(&self) -> bool {
+        self.min.is_finite() && self.max.is_finite()
+    }
+
     // Convenience functions (assumes origin is towards left top):
 
     pub fn left_top(&self) -> Pos2 {

emigui/src/region.rs

@@ -6,39 +6,49 @@ use crate::{font::TextFragment, layout::*, widgets::*, *};
 /// with a type of layout (horizontal or vertical).
 /// TODO: make Region a trait so we can have type-safe HorizontalRegion etc?
 pub struct Region {
+    // TODO: remove pub(crate) from all members.
+    //
+    /// How we access input, output and memory
     pub(crate) ctx: Arc<Context>,
 
     /// Where to put the graphics output of this Region
     pub(crate) layer: Layer,
 
-    pub(crate) style: Style,
+    /// ID of this region.
-
+    /// Generated based on id of parent region together with
-    /// Unique ID of this region.
+    /// another source of child identity (e.g. window title).
+    /// Acts like a namespace for child regions.
+    /// Hopefully unique.
     pub(crate) id: Id,
 
+    /// The `rect` represents where in space the region is
+    /// and its max size (original available_space).
+    /// Note that the size may be infinite in one or both dimensions.
+    /// The widgets will TRY to fit within the rect,
+    /// but may overflow (which you will see in bounding_size).
+    /// It will use the rect (which never changes) as a
+    /// clip rect when painting the contents of the region.
+    pub(crate) rect: Rect, // TODO: rename desired_rect
+
+    /// Bounding box of children.
+    /// We keep track of our max-size along the orthogonal to self.dir
+    /// Initially set to zero.
+    /// TODO: make into `child_bounds: Rect`
+    pub(crate) bounding_size: Vec2,
+
+    /// Overide default style in this region
+    pub(crate) style: Style,
+
+    // Layout stuff follows. TODO: move to own type and abstract.
     /// Doesn't change.
     pub(crate) dir: Direction,
 
     pub(crate) align: Align,
 
-    // The `rect` represents where in space the region is
-    // and its max size (original available_space).
-    // Note that the size may be infinite in one or both dimensions.
-    // The widgets will TRY to fit within the rect,
-    // but may overflow (which you will see in bounding_size).
-    // It will use the rect (which never changes) as a
-    // clip rect when painting the contents of the region.
-    pub(crate) rect: Rect,
-
     /// Where the next widget will be put.
     /// Progresses along self.dir.
     /// Initially set to rect.min()
     pub(crate) cursor: Pos2,
-
-    /// Bounding box of children.
-    /// We keep track of our max-size along the orthogonal to self.dir
-    /// Initially set to zero.
-    pub(crate) bounding_size: Vec2,
 }
 
 impl Region {

emigui/src/types.rs

@@ -120,10 +120,10 @@ pub enum PaintCmd {
         outline: Option<Outline>,
     },
     Rect {
+        rect: Rect,
         corner_radius: f32,
         fill_color: Option<Color>,
         outline: Option<Outline>,
-        rect: Rect,
     },
     /// Paint a single line of text
     Text {

emigui_glium/src/painter.rs

@@ -60,8 +60,8 @@ impl Painter {
                         void main() {
                             if (v_pos.x < v_clip_rect.x) { discard; }
                             if (v_pos.y < v_clip_rect.y) { discard; }
-                            // if (v_pos.x < v_clip_rect.z) { discard; } // TODO
+                            if (v_pos.x > v_clip_rect.z) { discard; }
-                            // if (v_pos.y > v_clip_rect.w) { discard; } // TODO
+                            if (v_pos.y > v_clip_rect.w) { discard; }
                             f_color = v_color;
                             f_color.rgb = linear_from_srgb(f_color.rgb);
                             f_color.a *= texture(u_sampler, v_tc).r;
@@ -86,8 +86,10 @@ impl Painter {
                                 1.0 - 2.0 * a_pos.y / u_screen_size.y,
                                 0.0,
                                 1.0);
+                            v_pos = a_pos;
                             v_color = a_color / 255.0;
                             v_tc = a_tc / u_tex_size;
+                            v_clip_rect = u_clip_rect;
                         }
                     ",
 
@@ -106,6 +108,10 @@ impl Painter {
                         }
 
                         void main() {
+                            if (v_pos.x < v_clip_rect.x) { discard; }
+                            if (v_pos.y < v_clip_rect.y) { discard; }
+                            if (v_pos.x > v_clip_rect.z) { discard; }
+                            if (v_pos.y > v_clip_rect.w) { discard; }
                             gl_FragColor = v_color;
                             gl_FragColor.rgb = linear_from_srgb(gl_FragColor.rgb);
                             gl_FragColor.a *= texture2D(u_sampler, v_tc).r;
@@ -130,8 +136,10 @@ impl Painter {
                                 1.0 - 2.0 * a_pos.y / u_screen_size.y,
                                 0.0,
                                 1.0);
+                            v_pos = a_pos;
                             v_color = a_color / 255.0;
                             v_tc = a_tc / u_tex_size;
+                            v_clip_rect = u_clip_rect;
                         }
                     ",
 
@@ -150,6 +158,10 @@ impl Painter {
                         }
 
                         void main() {
+                            if (v_pos.x < v_clip_rect.x) { discard; }
+                            if (v_pos.y < v_clip_rect.y) { discard; }
+                            if (v_pos.x > v_clip_rect.z) { discard; }
+                            if (v_pos.y > v_clip_rect.w) { discard; }
                             gl_FragColor = v_color;
                             gl_FragColor.rgb = linear_from_srgb(gl_FragColor.rgb);
                             gl_FragColor.a *= texture2D(u_sampler, v_tc).r;
@@ -247,8 +259,7 @@ impl Painter {
         let height_points = height_pixels as f32 / pixels_per_point;
 
         let uniforms = uniform! {
-            u_clip_rect_min: [clip_rect.min().x, clip_rect.min().y],
+            u_clip_rect: [clip_rect.min().x, clip_rect.min().y, clip_rect.max().x, clip_rect.max().y],
-            u_clip_rect_max: [clip_rect.max().x, clip_rect.max().y],
             u_screen_size: [width_points, height_points],
             u_tex_size: [texture.width as f32, texture.height as f32],
             u_sampler: &self.texture,