Drawable PR 3 - Layers (#1501)

Co-authored-by: Tim Sylvester <tim@wetdogweather.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

BUILD.bazel

@@ -1,6 +1,16 @@
 load("//bazel:flags.bzl", "CPP_FLAGS", "MAPLIBRE_FLAGS")
 load("@bazel_skylib//rules:common_settings.bzl", "string_flag")
-load("//bazel:core.bzl",
+load(
+    "//bazel:core.bzl",
+    "MLN_CORE_HEADERS",
+    "MLN_CORE_SOURCE",
+    "MLN_DRAWABLES_SOURCE",
+    "MLN_DRAWABLES_HEADERS",
+    "MLN_GENERATED_SHADER_HEADERS",
+    "MLN_GENERATED_STYLE_SOURCE",
+    "MLN_OPENGL_HEADERS",
+    "MLN_OPENGL_SOURCE",
+    "MLN_PRIVATE_GENERATED_STYLE_HEADERS",
     "MLN_PUBLIC_GENERATED_STYLE_HEADERS",
     "MLN_PRIVATE_GENERATED_STYLE_HEADERS",
     "MLN_GENERATED_STYLE_SOURCE",
@@ -83,17 +93,15 @@ cc_library(
 # the prefix from the path.
 cc_library(
     name = "mbgl-core",
-    srcs = MLN_CORE_SOURCE
-        + PREFIXED["MLN_GENERATED_STYLE_SOURCE"]
-        + MLN_OPENGL_SOURCE
-        + select({
+    srcs = MLN_CORE_SOURCE +
+           MLN_GENERATED_STYLE_SOURCE +
+           MLN_OPENGL_SOURCE + select({
             ":drawable_renderer": MLN_DRAWABLES_SOURCE,
             ":split_renderer": MLN_DRAWABLES_SOURCE,
-            "//conditions:default": []
+            "//conditions:default": [],
         }),
-    hdrs = MLN_CORE_HEADERS
-        + MLN_OPENGL_HEADERS
-        + select({
+    hdrs = MLN_CORE_HEADERS +
+           MLN_OPENGL_HEADERS + select({
             ":drawable_renderer": MLN_DRAWABLES_HEADERS,
             ":split_renderer": MLN_DRAWABLES_HEADERS,
             "//conditions:default": []

include/mbgl/gfx/drawable_builder.hpp

@@ -148,7 +148,6 @@ public:
 
     /// Add a triangle
     void addTriangle(int16_t x0, int16_t y0, int16_t x1, int16_t y1, int16_t x2, int16_t y2);
-
     /// Add another triangle based on the previous two points
     void appendTriangle(int16_t x0, int16_t y0);
 

include/mbgl/shaders/gl/drawable_hillshade_prepare.hpp

@@ -87,7 +87,7 @@ void main() {
     // we want to vertically exaggerate the hillshading though, because otherwise
     // it is barely noticeable at low zooms. to do this, we multiply this by some
     // scale factor pow(2, (u_zoom - u_maxzoom) * a) where a is an arbitrary value
-    // Here we use a=0.3 which works out to the expression below. see 
+    // Here we use a=0.3 which works out to the expression below. see
     // nickidlugash's awesome breakdown for more info
     // https://github.com/mapbox/mapbox-gl-js/pull/5286#discussion_r148419556
     float exaggeration = u_zoom < 2.0 ? 0.4 : u_zoom < 4.5 ? 0.35 : 0.3;

include/mbgl/shaders/gl/drawable_line_sdf.hpp

@@ -56,7 +56,7 @@ layout (std140) uniform LineSDFInterpolationUBO {
     lowp float u_offset_t;
     lowp float u_width_t;
     lowp float u_floorwidth_t;
-    
+
     highp float pad2;
 };
 
@@ -216,7 +216,7 @@ layout (std140) uniform LineSDFInterpolationUBO {
     lowp float u_offset_t;
     lowp float u_width_t;
     lowp float u_floorwidth_t;
-    
+
     highp float pad2;
 };
 

shaders/drawable.hillshade_prepare.fragment.glsl

@@ -56,7 +56,7 @@ void main() {
     // we want to vertically exaggerate the hillshading though, because otherwise
     // it is barely noticeable at low zooms. to do this, we multiply this by some
     // scale factor pow(2, (u_zoom - u_maxzoom) * a) where a is an arbitrary value
-    // Here we use a=0.3 which works out to the expression below. see 
+    // Here we use a=0.3 which works out to the expression below. see
     // nickidlugash's awesome breakdown for more info
     // https://github.com/mapbox/mapbox-gl-js/pull/5286#discussion_r148419556
     float exaggeration = u_zoom < 2.0 ? 0.4 : u_zoom < 4.5 ? 0.35 : 0.3;

shaders/drawable.line_sdf.fragment.glsl

@@ -32,7 +32,7 @@ layout (std140) uniform LineSDFInterpolationUBO {
     lowp float u_offset_t;
     lowp float u_width_t;
     lowp float u_floorwidth_t;
-    
+
     highp float pad2;
 };
 

shaders/drawable.line_sdf.vertex.glsl

@@ -46,7 +46,7 @@ layout (std140) uniform LineSDFInterpolationUBO {
     lowp float u_offset_t;
     lowp float u_width_t;
     lowp float u_floorwidth_t;
-    
+
     highp float pad2;
 };
 

src/mbgl/renderer/layers/render_heatmap_layer.cpp

@@ -202,23 +202,15 @@ void RenderHeatmapLayer::render(PaintParameters& parameters) {
 #endif // MLN_LEGACY_RENDERER
 
 void RenderHeatmapLayer::updateColorRamp() {
-    auto colorValue = unevaluated.get<HeatmapColor>().getValue();
-    if (colorValue.isUndefined()) {
-        colorValue = HeatmapLayer::getDefaultHeatmapColor();
-    }
+    if (colorRamp) {
+        auto colorValue = unevaluated.get<HeatmapColor>().getValue();
+        if (colorValue.isUndefined()) {
+            colorValue = HeatmapLayer::getDefaultHeatmapColor();
+        }
 
-    const auto length = (*colorRamp).bytes();
-
-    for (uint32_t i = 0; i < length; i += 4) {
-        const auto color = colorValue.evaluate(static_cast<double>(i) / length);
-        (*colorRamp).data[i + 0] = static_cast<uint8_t>(std::floor(color.r * 255.f));
-        (*colorRamp).data[i + 1] = static_cast<uint8_t>(std::floor(color.g * 255.f));
-        (*colorRamp).data[i + 2] = static_cast<uint8_t>(std::floor(color.b * 255.f));
-        (*colorRamp).data[i + 3] = static_cast<uint8_t>(std::floor(color.a * 255.f));
-    }
-
-    if (colorRampTexture) {
-        colorRampTexture = std::nullopt;
+        if (applyColorRamp(colorValue, *colorRamp)) {
+            colorRampTexture = std::nullopt;
+        }
     }
 }
 

src/mbgl/renderer/layers/render_line_layer.cpp

@@ -306,24 +306,12 @@ bool RenderLineLayer::queryIntersectsFeature(const GeometryCoordinates& queryGeo
 }
 
 void RenderLineLayer::updateColorRamp() {
-    auto colorValue = unevaluated.get<LineGradient>().getValue();
-    if (colorValue.isUndefined()) {
+    const style::ColorRampPropertyValue colorValue = unevaluated.get<LineGradient>().getValue();
+    if (!colorRamp || !applyColorRamp(colorValue, *colorRamp)) {
         return;
     }
 
-    const auto length = colorRamp->bytes();
-
-    for (uint32_t i = 0; i < length; i += 4) {
-        const auto color = colorValue.evaluate(static_cast<double>(i) / length);
-        colorRamp->data[i] = static_cast<uint8_t>(std::floor(color.r * 255.f));
-        colorRamp->data[i + 1] = static_cast<uint8_t>(std::floor(color.g * 255.f));
-        colorRamp->data[i + 2] = static_cast<uint8_t>(std::floor(color.b * 255.f));
-        colorRamp->data[i + 3] = static_cast<uint8_t>(std::floor(color.a * 255.f));
-    }
-
-    if (colorRampTexture) {
-        colorRampTexture = std::nullopt;
-    }
+    colorRampTexture = std::nullopt;
 
 #if MLN_DRAWABLE_RENDERER
     if (colorRampTexture2D) {

src/mbgl/renderer/render_layer.cpp

@@ -1,13 +1,14 @@
 #include <mbgl/renderer/render_layer.hpp>
 
+#include <mbgl/gfx/context.hpp>
 #include <mbgl/renderer/paint_parameters.hpp>
 #include <mbgl/renderer/render_source.hpp>
 #include <mbgl/renderer/render_tile.hpp>
-#include <mbgl/style/types.hpp>
+#include <mbgl/style/color_ramp_property_value.hpp>
 #include <mbgl/style/layer.hpp>
 #include <mbgl/style/layer_properties.hpp>
+#include <mbgl/style/types.hpp>
 #include <mbgl/tile/tile.hpp>
-#include <mbgl/gfx/context.hpp>
 #include <mbgl/util/logging.hpp>
 
 #if MLN_DRAWABLE_RENDERER
@@ -223,4 +224,21 @@ void RenderLayer::activateLayerGroup(const LayerGroupBasePtr& layerGroup_,
 }
 #endif
 
+bool RenderLayer::applyColorRamp(const style::ColorRampPropertyValue& colorValue, PremultipliedImage& image) {
+    if (colorValue.isUndefined()) {
+        return false;
+    }
+
+    const auto length = image.bytes();
+
+    for (uint32_t i = 0; i < length; i += 4) {
+        const auto color = colorValue.evaluate(static_cast<double>(i) / length);
+        image.data[i + 0] = static_cast<uint8_t>(std::floor(color.r * 255.f));
+        image.data[i + 1] = static_cast<uint8_t>(std::floor(color.g * 255.f));
+        image.data[i + 2] = static_cast<uint8_t>(std::floor(color.b * 255.f));
+        image.data[i + 3] = static_cast<uint8_t>(std::floor(color.a * 255.f));
+    }
+    return true;
+}
+
 } // namespace mbgl

src/mbgl/renderer/render_layer.hpp

@@ -51,6 +51,10 @@ using UniformBufferPtr = std::shared_ptr<UniformBuffer>;
 #endif
 } // namespace gfx
 
+namespace style {
+class ColorRampPropertyValue;
+} // namespace style
+
 class LayerRenderData {
 public:
     std::shared_ptr<Bucket> bucket;
@@ -212,13 +216,20 @@ protected:
     bool hasRenderTile(const OverscaledTileID&) const;
 
     /// Get the bucket ID from which a given tile was built
+    /// @details When a new style is loaded and contains a layer with the same ID, `layerChanged` will be called during
+    /// style
+    ///          parsing, but the `Bucket` in a tile's `RenderData` will only be replaced when the asynchronous load for
+    ///          the tile is complete, at which point the drawable for the tile may need to be updated or replaced.
     util::SimpleIdentity getRenderTileBucketID(const OverscaledTileID&) const;
 
     /// Set the bucket ID from which a given tile was built
-    /// @return true if updated, false if missing or unchanged
+    /// @return true if updated, false if the tile ID is not present in the set of tiles to be rendered or the ID is
+    /// unchanged
     bool setRenderTileBucketID(const OverscaledTileID&, util::SimpleIdentity bucketID);
 #endif // MLN_DRAWABLE_RENDERER
 
+    static bool applyColorRamp(const style::ColorRampPropertyValue&, PremultipliedImage&);
+
 protected:
     // Stores current set of tiles to be rendered for this layer.
     RenderTiles renderTiles;