1 files changed, 84 insertions, 0 deletions
diff --git a/src/mbgl/renderer/painter_terrain.cpp b/src/mbgl/renderer/painter_terrain.cpp
new file mode 100644
index 000000000..c59182c2e
--- /dev/null
+++ b/src/mbgl/renderer/painter_terrain.cpp
@@ -0,0 +1,84 @@
+#include <mbgl/renderer/painter.hpp>
+#include <mbgl/renderer/paint_parameters.hpp>
+#include <mbgl/renderer/render_tile.hpp>
+#include <mbgl/gl/gl.hpp>
+#include <mbgl/renderer/terrain_bucket.hpp>
+#include <mbgl/style/layers/terrain_layer.hpp>
+#include <mbgl/style/layers/terrain_layer_impl.hpp>
+#include <mbgl/shader/shaders.hpp>
+#include <mbgl/util/offscreen_texture.hpp>
+
+namespace mbgl {
+
+using namespace style;
+
+void Painter::renderTerrain(PaintParameters& parameters,
+                           TerrainBucket& bucket,
+                           const TerrainLayer& layer,
+                           const RenderTile& tile) {
+    if (pass != RenderPass::Translucent) return;
+
+    if (!bucket.prepared) {
+        OffscreenTexture view(context, { 256, 256 });
+        view.bind();
+
+        context.bindTexture(*bucket.dem, 0, gl::TextureFilter::Linear, gl::TextureMipMap::Yes);
+
+        mat4 mat;
+        matrix::ortho(mat, 0, util::EXTENT, -util::EXTENT, 0, 0, 1);
+        matrix::translate(mat, mat, 0, -util::EXTENT, 0);
+
+        context.clear(Color::red(), {}, {});
+        context.draw({
+            gl::DepthMode::disabled(),
+            gl::StencilMode::disabled(),
+            gl::ColorMode::unblended(),
+            parameters.shaders.terrainPrepare,
+            TerrainPrepareUniforms::Values {
+                mat,
+                0,
+                { {{ 512, 512 }} },
+                tile.id.canonical.z
+            },
+            gl::Unindexed<gl::TriangleStrip>(rasterVertexBuffer)
+        });
+
+        bucket.texture = std::move(view.getTexture());
+        bucket.prepared = true;
+
+        parameters.view.bind();
+    }
+
+    const TerrainPaintProperties& properties = layer.impl->paint;
+
+        double azimuth = (-properties.terrainIlluminationDirection - 90) * util::DEG2RAD;
+        if (properties.terrainIlluminationAlignment == style::AlignmentType::Viewport) {
+            azimuth -= state.getAngle();
+        }
+
+    context.bindTexture(*bucket.texture, 0, gl::TextureFilter::Linear);
+
+    context.draw({
+        depthModeForSublayer(0, gl::DepthMode::ReadOnly),
+        stencilModeForClipping(tile.clip),
+        colorModeForRenderPass(),
+        parameters.shaders.terrain,
+        TerrainUniforms::Values {
+            tile.matrix,
+            0, // image
+            8, // mode
+            { {{ 256, 256 }} },
+            tile.id.canonical.z,
+            azimuth,
+            60 * util::DEG2RAD, // zenith
+            0, // mipmap
+            properties.terrainExaggeration.value,
+            properties.terrainShadowColor.value,
+            properties.terrainHighlightColor.value,
+            properties.terrainAccentColor.value
+        },
+        gl::Unindexed<gl::TriangleStrip>(rasterVertexBuffer)
+    });
+}
+
+} // namespace mbgl