1 files changed, 145 insertions, 0 deletions
diff --git a/src/mbgl/programs/symbol_program.cpp b/src/mbgl/programs/symbol_program.cpp
new file mode 100644
index 0000000000..8c9c34210c
--- /dev/null
+++ b/src/mbgl/programs/symbol_program.cpp
@@ -0,0 +1,145 @@
+#include <mbgl/programs/symbol_program.hpp>
+#include <mbgl/renderer/render_tile.hpp>
+#include <mbgl/map/transform_state.hpp>
+#include <mbgl/style/layers/symbol_layer_impl.hpp>
+
+namespace mbgl {
+
+using namespace style;
+
+static_assert(sizeof(SymbolAttributes::Vertex) == 16, "expected SymbolVertex size");
+
+template <class Values, class...Args>
+Values makeValues(const style::SymbolPropertyValues& values,
+                  const Size& texsize,
+                  const std::array<float, 2>& pixelsToGLUnits,
+                  const RenderTile& tile,
+                  const TransformState& state,
+                  Args&&... args) {
+    std::array<float, 2> extrudeScale;
+
+    const float scale = values.paintSize / values.sdfScale;
+    if (values.pitchAlignment == AlignmentType::Map) {
+        extrudeScale.fill(tile.id.pixelsToTileUnits(1, state.getZoom()) * scale);
+    } else {
+        extrudeScale = {{
+            pixelsToGLUnits[0] * scale * state.getAltitude(),
+            pixelsToGLUnits[1] * scale * state.getAltitude()
+        }};
+    }
+
+    // adjust min/max zooms for variable font sies
+    float zoomAdjust = std::log(values.paintSize / values.layoutSize) / std::log(2);
+
+    return Values {
+        uniforms::u_matrix::Value{ tile.translatedMatrix(values.translate,
+                                   values.translateAnchor,
+                                   state) },
+        uniforms::u_opacity::Value{ values.opacity },
+        uniforms::u_extrude_scale::Value{ extrudeScale },
+        uniforms::u_texsize::Value{ std::array<float, 2> {{ float(texsize.width) / 4, float(texsize.height) / 4 }} },
+        uniforms::u_zoom::Value{ float((state.getZoom() - zoomAdjust) * 10) },
+        uniforms::u_rotate_with_map::Value{ values.rotationAlignment == AlignmentType::Map },
+        uniforms::u_texture::Value{ 0 },
+        uniforms::u_fadetexture::Value{ 1 },
+        std::forward<Args>(args)...
+    };
+}
+
+SymbolIconProgram::UniformValues
+SymbolIconProgram::uniformValues(const style::SymbolPropertyValues& values,
+                                 const Size& texsize,
+                                 const std::array<float, 2>& pixelsToGLUnits,
+                                 const RenderTile& tile,
+                                 const TransformState& state)
+{
+    return makeValues<SymbolIconProgram::UniformValues>(
+        values,
+        texsize,
+        pixelsToGLUnits,
+        tile,
+        state
+    );
+}
+
+static SymbolSDFProgram::UniformValues makeSDFValues(const style::SymbolPropertyValues& values,
+                                               const Size& texsize,
+                                               const std::array<float, 2>& pixelsToGLUnits,
+                                               const RenderTile& tile,
+                                               const TransformState& state,
+                                               float pixelRatio,
+                                               Color color,
+                                               float buffer,
+                                               float gammaAdjust)
+{
+    // The default gamma value has to be adjust for the current pixelratio so that we're not
+    // drawing blurry font on retina screens.
+    const float gammaBase = 0.105 * values.sdfScale / values.paintSize / pixelRatio;
+    const float gammaScale = values.pitchAlignment == AlignmentType::Map
+        ? 1.0 / std::cos(state.getPitch())
+        : 1.0;
+
+    return makeValues<SymbolSDFProgram::UniformValues>(
+        values,
+        texsize,
+        pixelsToGLUnits,
+        tile,
+        state,
+        uniforms::u_color::Value{ color },
+        uniforms::u_buffer::Value{ buffer },
+        uniforms::u_gamma::Value{ (gammaBase + gammaAdjust) * gammaScale },
+        uniforms::u_pitch::Value{ state.getPitch() },
+        uniforms::u_bearing::Value{ -1.0f * state.getAngle() },
+        uniforms::u_aspect_ratio::Value{ (state.getSize().width * 1.0f) / (state.getSize().height * 1.0f) },
+        uniforms::u_pitch_with_map::Value{ values.pitchAlignment == AlignmentType::Map }
+    );
+}
+
+SymbolSDFProgram::UniformValues
+SymbolSDFProgram::haloUniformValues(const style::SymbolPropertyValues& values,
+                              const Size& texsize,
+                              const std::array<float, 2>& pixelsToGLUnits,
+                              const RenderTile& tile,
+                              const TransformState& state,
+                              float pixelRatio)
+{
+    const float scale = values.paintSize / values.sdfScale;
+    const float sdfPx = 8.0f;
+    const float blurOffset = 1.19f;
+    const float haloOffset = 6.0f;
+
+    return makeSDFValues(
+        values,
+        texsize,
+        pixelsToGLUnits,
+        tile,
+        state,
+        pixelRatio,
+        values.haloColor,
+        (haloOffset - values.haloWidth / scale) / sdfPx,
+        values.haloBlur * blurOffset / scale / sdfPx
+    );
+}
+
+SymbolSDFProgram::UniformValues
+SymbolSDFProgram::foregroundUniformValues(const style::SymbolPropertyValues& values,
+                                    const Size& texsize,
+                                    const std::array<float, 2>& pixelsToGLUnits,
+                                    const RenderTile& tile,
+                                    const TransformState& state,
+                                    float pixelRatio)
+{
+    return makeSDFValues(
+        values,
+        texsize,
+        pixelsToGLUnits,
+        tile,
+        state,
+        pixelRatio,
+        values.color,
+        (256.0f - 64.0f) / 256.0f,
+        0
+    );
+}
+
+} // namespace mbgl