system/ui: GPU-accelerated polygon rendering with anti-aliasing and gradients (#35357)

* Add GPU-accelerated polygon rendering with anti-aliased edges and gradient support

* use np array

* update ModelRenderer

* ndarray

* cleanup

* improve shader

* Revert "improve shader"

This reverts commit 992247617a.

* improve shader for smoother edges

system/ui/lib/shader_polygon.py

@@ -0,0 +1,338 @@
+import pyray as rl
+import numpy as np
+from typing import Any
+
+
+FRAGMENT_SHADER = """
+#version 300 es
+precision mediump float;
+
+in vec2 fragTexCoord;
+out vec4 finalColor;
+
+uniform vec2 points[100];
+uniform int pointCount;
+uniform vec4 fillColor;
+uniform vec2 resolution;
+
+uniform bool useGradient;
+uniform vec2 gradientStart;
+uniform vec2 gradientEnd;
+uniform vec4 gradientColors[8];
+uniform float gradientStops[8];
+uniform int gradientColorCount;
+
+vec4 getGradientColor(vec2 pos) {
+  vec2 gradientDir = gradientEnd - gradientStart;
+  float gradientLength = length(gradientDir);
+
+  if (gradientLength < 0.001) return gradientColors[0];
+
+  vec2 normalizedDir = gradientDir / gradientLength;
+  vec2 pointVec = pos - gradientStart;
+  float projection = dot(pointVec, normalizedDir);
+  float t = clamp(projection / gradientLength, 0.0, 1.0);
+
+  for (int i = 0; i < gradientColorCount - 1; i++) {
+    if (t >= gradientStops[i] && t <= gradientStops[i+1]) {
+      float segmentT = (t - gradientStops[i]) / (gradientStops[i+1] - gradientStops[i]);
+      return mix(gradientColors[i], gradientColors[i+1], segmentT);
+    }
+  }
+
+  return gradientColors[gradientColorCount-1];
+}
+
+bool isPointInsidePolygon(vec2 p) {
+  if (pointCount < 3) return false;
+
+  if (pointCount == 3) {
+    vec2 v0 = points[0];
+    vec2 v1 = points[1];
+    vec2 v2 = points[2];
+
+    float d = (v1.y - v2.y) * (v0.x - v2.x) + (v2.x - v1.x) * (v0.y - v2.y);
+    if (abs(d) < 0.0001) return false;
+
+    float a = ((v1.y - v2.y) * (p.x - v2.x) + (v2.x - v1.x) * (p.y - v2.y)) / d;
+    float b = ((v2.y - v0.y) * (p.x - v2.x) + (v0.x - v2.x) * (p.y - v2.y)) / d;
+    float c = 1.0 - a - b;
+
+    return (a >= 0.0 && b >= 0.0 && c >= 0.0);
+  }
+
+  bool inside = false;
+  for (int i = 0, j = pointCount - 1; i < pointCount; j = i++) {
+    if (distance(points[i], points[j]) < 0.0001) continue;
+
+    float dy = points[j].y - points[i].y;
+    if (abs(dy) < 0.0001) continue;
+
+    if (((points[i].y > p.y) != (points[j].y > p.y))) {
+      float x_intersect = points[i].x + (points[j].x - points[i].x) * (p.y - points[i].y) / dy;
+      if (p.x < x_intersect) {
+        inside = !inside;
+      }
+    }
+  }
+  return inside;
+}
+
+float distanceToEdge(vec2 p) {
+  float minDist = 1000.0;
+
+  for (int i = 0, j = pointCount - 1; i < pointCount; j = i++) {
+    vec2 edge0 = points[j];
+    vec2 edge1 = points[i];
+
+    if (distance(edge0, edge1) < 0.0001) continue;
+
+    vec2 v1 = p - edge0;
+    vec2 v2 = edge1 - edge0;
+    float l2 = dot(v2, v2);
+
+    if (l2 < 0.0001) {
+      float dist = length(v1);
+      minDist = min(minDist, dist);
+      continue;
+    }
+
+    float t = clamp(dot(v1, v2) / l2, 0.0, 1.0);
+    vec2 projection = edge0 + t * v2;
+    float dist = length(p - projection);
+    minDist = min(minDist, dist);
+  }
+
+  return minDist;
+}
+
+float signedDistanceToPolygon(vec2 p) {
+  float dist = distanceToEdge(p);
+  bool inside = isPointInsidePolygon(p);
+  return inside ? dist : -dist;
+}
+
+void main() {
+  vec2 pixel = fragTexCoord * resolution;
+
+  float signedDist = signedDistanceToPolygon(pixel);
+
+  vec2 pixelGrad = vec2(dFdx(pixel.x), dFdy(pixel.y));
+  float pixelSize = length(pixelGrad);
+  float aaWidth = max(0.5, pixelSize * 1.0);
+
+  float alpha = smoothstep(-aaWidth, aaWidth, signedDist);
+
+  if (alpha > 0.0) {
+    vec4 color;
+    if (useGradient) {
+      color = getGradientColor(fragTexCoord);
+    } else {
+      color = fillColor;
+    }
+    finalColor = vec4(color.rgb, color.a * alpha);
+  } else {
+    finalColor = vec4(0.0, 0.0, 0.0, 0.0);
+  }
+}
+"""
+
+# Default vertex shader
+VERTEX_SHADER = """
+#version 300 es
+in vec3 vertexPosition;
+in vec2 vertexTexCoord;
+out vec2 fragTexCoord;
+uniform mat4 mvp;
+
+void main() {
+  fragTexCoord = vertexTexCoord;
+  gl_Position = mvp * vec4(vertexPosition, 1.0);
+}
+"""
+
+
+class ShaderState:
+  _instance: Any  = None
+
+  @classmethod
+  def get_instance(cls):
+    if cls._instance is None:
+      cls._instance = cls()
+    return cls._instance
+
+  def __init__(self):
+    if ShaderState._instance is not None:
+      raise Exception("This class is a singleton. Use get_instance() instead.")
+
+    self.initialized = False
+    self.shader = None
+    self.white_texture = None
+
+    # Shader uniform locations
+    self.locations = {
+      'pointCount': None,
+      'fillColor': None,
+      'resolution': None,
+      'points': None,
+      'useGradient': None,
+      'gradientStart': None,
+      'gradientEnd': None,
+      'gradientColors': None,
+      'gradientStops': None,
+      'gradientColorCount': None,
+      'mvp': None,
+    }
+
+  def initialize(self):
+    if self.initialized:
+      return
+
+    vertex_shader = rl.load_shader_from_memory(VERTEX_SHADER, FRAGMENT_SHADER)
+    self.shader = vertex_shader
+
+    # Create and cache white texture
+    white_img = rl.gen_image_color(2, 2, rl.WHITE)
+    self.white_texture = rl.load_texture_from_image(white_img)
+    rl.set_texture_filter(self.white_texture, rl.TEXTURE_FILTER_BILINEAR)
+    rl.unload_image(white_img)
+
+    # Cache all uniform locations
+    for uniform in self.locations.keys():
+      self.locations[uniform] = rl.get_shader_location(self.shader, uniform)
+
+    # Setup default MVP matrix
+    mvp_ptr = rl.ffi.new("float[16]", [1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0])
+    rl.set_shader_value_matrix(self.shader, self.locations['mvp'], rl.Matrix(*mvp_ptr))
+
+    self.initialized = True
+
+  def cleanup(self):
+    if not self.initialized:
+      return
+
+    if self.white_texture:
+      rl.unload_texture(self.white_texture)
+      self.white_texture = None
+
+    if self.shader:
+      rl.unload_shader(self.shader)
+      self.shader = None
+
+    self.initialized = False
+
+
+def draw_polygon(points: np.ndarray, color=None, gradient=None):
+  """
+  Draw a complex polygon using shader-based even-odd fill rule
+
+  Args:
+      points: List of (x,y) points defining the polygon
+      color: Solid fill color (rl.Color)
+      gradient: Dict with gradient parameters:
+          {
+              'start': (x1, y1),    # Start point (normalized 0-1)
+              'end': (x2, y2),      # End point (normalized 0-1)
+              'colors': [rl.Color], # List of colors at stops
+              'stops': [float]      # List of positions (0-1)
+          }
+  """
+  if len(points) < 3:
+    return
+
+  # Get shader state singleton
+  state = ShaderState.get_instance()
+
+  # Initialize shader if not already done
+  if not state.initialized:
+    state.initialize()
+
+  # Find bounding box
+  min_xy = np.min(points, axis=0)
+  min_x, min_y = min_xy
+  max_x, max_y = np.max(points, axis=0)
+
+  width = max(1, max_x - min_x)
+  height = max(1, max_y - min_y)
+
+  # Transform points to shader space
+  transformed_points = points - min_xy
+
+  # Set basic shader uniforms using cached locations
+  point_count_ptr = rl.ffi.new("int[]", [len(transformed_points)])
+  rl.set_shader_value(state.shader, state.locations['pointCount'], point_count_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_INT)
+
+  resolution_ptr = rl.ffi.new("float[]", [width, height])
+  rl.set_shader_value(state.shader, state.locations['resolution'], resolution_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_VEC2)
+
+  # Set points
+  flat_points = np.ascontiguousarray(transformed_points.flatten().astype(np.float32))
+  points_ptr = rl.ffi.cast("float *", flat_points.ctypes.data)
+  rl.set_shader_value_v(
+    state.shader, state.locations['points'], points_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_VEC2, len(transformed_points)
+  )
+
+  # Set gradient or solid color based on what was provided
+  if gradient:
+    # Enable gradient
+    use_gradient_ptr = rl.ffi.new("int[]", [1])
+    rl.set_shader_value(state.shader, state.locations['useGradient'], use_gradient_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_INT)
+
+    # Set gradient start/end
+    start_ptr = rl.ffi.new("float[]", [gradient['start'][0], gradient['start'][1]])
+    end_ptr = rl.ffi.new("float[]", [gradient['end'][0], gradient['end'][1]])
+    rl.set_shader_value(state.shader, state.locations['gradientStart'], start_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_VEC2)
+    rl.set_shader_value(state.shader, state.locations['gradientEnd'], end_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_VEC2)
+
+    # Set gradient colors
+    colors = gradient['colors']
+    color_count = min(len(colors), 8)  # Max 8 colors
+    colors_ptr = rl.ffi.new("float[]", color_count * 4)
+    for i, c in enumerate(colors[:color_count]):
+      colors_ptr[i * 4] = c.r / 255.0
+      colors_ptr[i * 4 + 1] = c.g / 255.0
+      colors_ptr[i * 4 + 2] = c.b / 255.0
+      colors_ptr[i * 4 + 3] = c.a / 255.0
+    rl.set_shader_value_v(
+      state.shader, state.locations['gradientColors'], colors_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_VEC4, color_count
+    )
+
+    # Set gradient stops
+    stops = gradient.get('stops', [i / (color_count - 1) for i in range(color_count)])
+    stops_ptr = rl.ffi.new("float[]", color_count)
+    for i, s in enumerate(stops[:color_count]):
+      stops_ptr[i] = s
+    rl.set_shader_value_v(
+      state.shader, state.locations['gradientStops'], stops_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_FLOAT, color_count
+    )
+
+    # Set color count
+    color_count_ptr = rl.ffi.new("int[]", [color_count])
+    rl.set_shader_value(state.shader, state.locations['gradientColorCount'], color_count_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_INT)
+  else:
+    # Disable gradient
+    use_gradient_ptr = rl.ffi.new("int[]", [0])
+    rl.set_shader_value(state.shader, state.locations['useGradient'], use_gradient_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_INT)
+
+    # Set solid color
+    if color is None:
+      color = rl.WHITE
+    fill_color_ptr = rl.ffi.new("float[]", [color.r / 255.0, color.g / 255.0, color.b / 255.0, color.a / 255.0])
+    rl.set_shader_value(state.shader, state.locations['fillColor'], fill_color_ptr, rl.ShaderUniformDataType.SHADER_UNIFORM_VEC4)
+
+  # Draw with shader
+  rl.begin_shader_mode(state.shader)
+  rl.draw_texture_pro(
+    state.white_texture,
+    rl.Rectangle(0, 0, 2, 2),
+    rl.Rectangle(int(min_x), int(min_y), int(width), int(height)),
+    rl.Vector2(0, 0),
+    0.0,
+    rl.WHITE,
+  )
+  rl.end_shader_mode()
+
+
+def cleanup_shader_resources():
+  state = ShaderState.get_instance()
+  state.cleanup()

system/ui/onroad/model_renderer.py

@@ -4,6 +4,7 @@ import numpy as np
 import pyray as rl
 from cereal import messaging, car
 from openpilot.common.params import Params
+from openpilot.system.ui.lib.shader_polygon import draw_polygon
 
 
 CLIP_MARGIN = 500
@@ -30,14 +31,14 @@ class ModelRenderer:
     self._experimental_mode = False
     self._blend_factor = 1.0
     self._prev_allow_throttle = True
-    self._lane_line_probs = [0.0] * 4
-    self._road_edge_stds = [0.0] * 2
+    self._lane_line_probs = np.zeros(4, dtype=np.float32)
+    self._road_edge_stds = np.zeros(2, dtype=np.float32)
     self._path_offset_z = 1.22
 
     # Initialize empty polygon vertices
-    self._track_vertices = []
-    self._lane_line_vertices = [[] for _ in range(4)]
-    self._road_edge_vertices = [[] for _ in range(2)]
+    self._track_vertices = np.empty((0, 2), dtype=np.float32)
+    self._lane_line_vertices = [np.empty((0, 2), dtype=np.float32) for _ in range(4)]
+    self._road_edge_vertices = [np.empty((0, 2), dtype=np.float32) for _ in range(2)]
     self._lead_vertices = [None, None]
 
     # Transform matrix (3x3 for car space to screen space)
@@ -145,29 +146,29 @@ class ModelRenderer:
 
   def _draw_lane_lines(self):
     """Draw lane lines and road edges"""
-    for i in range(4):
+    for i, vertices in enumerate(self._lane_line_vertices):
       # Skip if no vertices
-      if not self._lane_line_vertices[i]:
+      if vertices.size == 0:
         continue
 
       # Draw lane line
       alpha = np.clip(self._lane_line_probs[i], 0.0, 0.7)
       color = rl.Color(255, 255, 255, int(alpha * 255))
-      self._draw_polygon(self._lane_line_vertices[i], color)
+      draw_polygon(vertices, color)
 
-    for i in range(2):
+    for i, vertices in enumerate(self._road_edge_vertices):
       # Skip if no vertices
-      if not self._road_edge_vertices[i]:
+      if vertices.size == 0:
         continue
 
       # Draw road edge
       alpha = np.clip(1.0 - self._road_edge_stds[i], 0.0, 1.0)
       color = rl.Color(255, 0, 0, int(alpha * 255))
-      self._draw_polygon(self._road_edge_vertices[i], color)
+      draw_polygon(vertices, color)
 
   def _draw_path(self, sm, model, height):
     """Draw the path polygon with gradient based on acceleration"""
-    if not self._track_vertices:
+    if self._track_vertices.size == 0:
       return
 
     if self._experimental_mode:
@@ -175,16 +176,29 @@ class ModelRenderer:
       acceleration = model.acceleration.x
       max_len = min(len(self._track_vertices) // 2, len(acceleration))
 
-      # Create gradient colors for path sections
-      for i in range(max_len):
+      # Find midpoint index for polygon
+      mid_point = len(self._track_vertices) // 2
+
+      # For acceleration-based coloring, process segments separately
+      left_side = self._track_vertices[:mid_point]
+      right_side = self._track_vertices[mid_point:][::-1]  # Reverse for proper winding
+
+      # Create segments for gradient coloring
+      segment_colors = []
+      gradient_stops = []
+
+      for i in range(max_len - 1):
+        if i >= len(left_side) - 1 or i >= len(right_side) - 1:
+          break
+
         track_idx = max_len - i - 1  # flip idx to start from bottom right
-        track_y = self._track_vertices[track_idx][1]
+
         # Skip points out of frame
-        if track_y < 0 or track_y > height:
+        if left_side[track_idx][1] < 0 or left_side[track_idx][1] > height:
           continue
 
         # Calculate color based on acceleration
-        lin_grad_point = (height - track_y) / height
+        lin_grad_point = (height - left_side[track_idx][1]) / height
 
         # speed up: 120, slow down: 0
         path_hue = max(min(60 + acceleration[i] * 35, 120), 0)
@@ -197,12 +211,22 @@ class ModelRenderer:
         # Use HSL to RGB conversion
         color = self._hsla_to_color(path_hue / 360.0, saturation, lightness, alpha)
 
-        # TODO: This is simplified - a full implementation would create a gradient fill
-        segment = self._track_vertices[track_idx : track_idx + 2] + self._track_vertices[-track_idx - 2 : -track_idx]
-        self._draw_polygon(segment, color)
-
-        # Skip a point, unless next is last
-        i += 1 if i + 2 < max_len else 0
+        # Create quad segment
+        gradient_stops.append(lin_grad_point)
+        segment_colors.append(color)
+
+      if len(segment_colors) < 2:
+        draw_polygon(self._track_vertices, rl.Color(255, 255, 255, 30))
+        return
+
+      # Create gradient specification
+      gradient = {
+        'start': (0.0, 1.0),  # Bottom of path
+        'end': (0.0, 0.0),  # Top of path
+        'colors': segment_colors,
+        'stops': gradient_stops,
+      }
+      draw_polygon(self._track_vertices, gradient=gradient)
     else:
       # Draw with throttle/no throttle gradient
       allow_throttle = sm['longitudinalPlan'].allowThrottle or not self._longitudinal_control
@@ -226,7 +250,13 @@ class ModelRenderer:
         self._blend_colors(begin_colors[2], end_colors[2], self._blend_factor),
       ]
 
-      self._draw_polygon(self._track_vertices, colors[0])
+      gradient = {
+        'start': (0.0, 1.0),  # Bottom of path
+        'end': (0.0, 0.0),  # Top of path
+        'colors': colors,
+        'stops': [0.0, 1.0],
+      }
+      draw_polygon(self._track_vertices, gradient=gradient)
 
   def _draw_lead(self, lead_data, vd, rect):
     """Draw lead vehicle indicator"""
@@ -284,14 +314,14 @@ class ModelRenderer:
 
     return (x, y)
 
-  def _map_line_to_polygon(self, line, y_off, z_off, max_idx, allow_invert=True):
+  def _map_line_to_polygon(self, line, y_off, z_off, max_idx, allow_invert=True)-> np.ndarray:
     """Convert a 3D line to a 2D polygon for drawing"""
     line_x = line.x
     line_y = line.y
     line_z = line.z
 
-    left_points = []
-    right_points = []
+    left_points: list[tuple[float, float]] = []
+    right_points: list[tuple[float, float]] = []
 
     for i in range(max_idx + 1):
       # Skip points with negative x (behind camera)
@@ -309,23 +339,10 @@ class ModelRenderer:
         left_points.append(left)
         right_points.append(right)
 
-    if not left_points:
-      return []
-
-    return left_points + right_points[::-1]
-
-  def _draw_polygon(self, points, color):
-    # TODO: Enhance polygon drawing to support even-odd fill rule efficiently, as Raylib lacks native support.
-    #       Use a faster triangulation algorithm (e.g., ear clipping) or GPU shader for
-    #       efficient rendering of lane lines, road edges, and path polygons.
-    if len(points) <= 8:
-      rl.draw_triangle_fan(points, len(points), color)
-    else:
-      for i in range(1, len(points) - 1):
-        rl.draw_triangle(points[0], points[i], points[i + 1], color)
+    if not left_points or not right_points:
+      return np.empty((0, 2), dtype=np.float32)
 
-    for i in range(len(points)):
-      rl.draw_line_ex(points[i], points[(i + 1) % len(points)], 1.5, color)
+    return np.array(left_points + right_points[::-1], dtype=np.float32)
 
   @staticmethod
   def _map_val(x, x0, x1, y0, y1):