ui pipeline

ui/render.sx

@@ -0,0 +1,180 @@
+#import "modules/std.sx";
+#import "ui/types.sx";
+
+RenderNodeType :: enum {
+    rect;
+    rounded_rect;
+    text;
+    image;
+    clip_push;
+    clip_pop;
+    opacity_push;
+    opacity_pop;
+}
+
+RenderNode :: struct {
+    type: RenderNodeType;
+    frame: Frame;
+
+    // Rect / rounded_rect
+    fill_color: Color;
+    stroke_color: Color;
+    stroke_width: f32;
+    corner_radius: f32;
+
+    // Text
+    text: string;
+    font_size: f32;
+    text_color: Color;
+
+    // Image
+    texture_id: u32;
+
+    // Opacity
+    opacity: f32;
+
+    depth: s64;
+}
+
+RenderTree :: struct {
+    nodes: List(RenderNode);
+    generation: s64;
+
+    init :: () -> RenderTree {
+        RenderTree.{ generation = 0 };
+    }
+
+    clear :: (self: *RenderTree) {
+        self.nodes.len = 0;
+        self.generation += 1;
+    }
+
+    add :: (self: *RenderTree, node: RenderNode) -> s64 {
+        idx := self.nodes.len;
+        self.nodes.append(node);
+        idx;
+    }
+}
+
+// Stateful builder — views use this to emit render nodes
+
+RenderContext :: struct {
+    tree: *RenderTree;
+    clip_depth: s64;
+    opacity: f32;
+    depth: s64;
+
+    init :: (tree: *RenderTree) -> RenderContext {
+        RenderContext.{
+            tree = tree,
+            clip_depth = 0,
+            opacity = 1.0,
+            depth = 0
+        };
+    }
+
+    add_rect :: (self: *RenderContext, frame: Frame, fill: Color) {
+        node : RenderNode = ---;
+        memset(@node, 0, size_of(RenderNode));
+        node.type = .rect;
+        node.frame = frame;
+        node.fill_color = fill;
+        node.opacity = self.opacity;
+        node.depth = self.depth;
+        self.tree.add(node);
+        self.depth += 1;
+    }
+
+    add_rounded_rect :: (self: *RenderContext, frame: Frame, fill: Color, radius: f32) {
+        node : RenderNode = ---;
+        memset(@node, 0, size_of(RenderNode));
+        node.type = .rounded_rect;
+        node.frame = frame;
+        node.fill_color = fill;
+        node.corner_radius = radius;
+        node.opacity = self.opacity;
+        node.depth = self.depth;
+        self.tree.add(node);
+        self.depth += 1;
+    }
+
+    add_stroked_rect :: (self: *RenderContext, frame: Frame, fill: Color, stroke: Color, stroke_w: f32, radius: f32) {
+        node : RenderNode = ---;
+        memset(@node, 0, size_of(RenderNode));
+        node.type = .rounded_rect;
+        node.frame = frame;
+        node.fill_color = fill;
+        node.stroke_color = stroke;
+        node.stroke_width = stroke_w;
+        node.corner_radius = radius;
+        node.opacity = self.opacity;
+        node.depth = self.depth;
+        self.tree.add(node);
+        self.depth += 1;
+    }
+
+    add_text :: (self: *RenderContext, frame: Frame, text: string, font_size: f32, color: Color) {
+        node : RenderNode = ---;
+        memset(@node, 0, size_of(RenderNode));
+        node.type = .text;
+        node.frame = frame;
+        node.text = text;
+        node.font_size = font_size;
+        node.text_color = color;
+        node.opacity = self.opacity;
+        node.depth = self.depth;
+        self.tree.add(node);
+        self.depth += 1;
+    }
+
+    add_image :: (self: *RenderContext, frame: Frame, texture_id: u32) {
+        node : RenderNode = ---;
+        memset(@node, 0, size_of(RenderNode));
+        node.type = .image;
+        node.frame = frame;
+        node.texture_id = texture_id;
+        node.opacity = self.opacity;
+        node.depth = self.depth;
+        self.tree.add(node);
+        self.depth += 1;
+    }
+
+    push_clip :: (self: *RenderContext, frame: Frame) {
+        node : RenderNode = ---;
+        memset(@node, 0, size_of(RenderNode));
+        node.type = .clip_push;
+        node.frame = frame;
+        node.depth = self.depth;
+        self.tree.add(node);
+        self.clip_depth += 1;
+    }
+
+    pop_clip :: (self: *RenderContext) {
+        node : RenderNode = ---;
+        memset(@node, 0, size_of(RenderNode));
+        node.type = .clip_pop;
+        node.depth = self.depth;
+        self.tree.add(node);
+        self.clip_depth -= 1;
+    }
+
+    push_opacity :: (self: *RenderContext, alpha: f32) {
+        prev := self.opacity;
+        self.opacity = prev * alpha;
+        node : RenderNode = ---;
+        memset(@node, 0, size_of(RenderNode));
+        node.type = .opacity_push;
+        node.opacity = self.opacity;
+        node.depth = self.depth;
+        self.tree.add(node);
+    }
+
+    pop_opacity :: (self: *RenderContext, prev_opacity: f32) {
+        node : RenderNode = ---;
+        memset(@node, 0, size_of(RenderNode));
+        node.type = .opacity_pop;
+        node.depth = self.depth;
+        self.tree.add(node);
+        self.opacity = prev_opacity;
+    }
+}