[core] Remove obsolete modular arithmetic on atlas coordinates

We switched to 16-bit coordinates in attributes in b0cb8715ed74678b4d0f05829fa71a590e41b2f6, so there's no longer any reason to require that they are divisible by four.

4 files changed, 10 insertions, 23 deletions

diff --git a/src/mbgl/programs/symbol_program.cpp b/src/mbgl/programs/symbol_program.cpp
index 86f61c4ad2..1fb4ae5c5e 100644
--- a/src/mbgl/programs/symbol_program.cpp
+++ b/src/mbgl/programs/symbol_program.cpp
@@ -51,7 +51,7 @@ Values makeValues(const bool isText,
                                    values.translateAnchor,
                                    state) },
         uniforms::u_extrude_scale::Value{ extrudeScale },
-        uniforms::u_texsize::Value{ std::array<float, 2> {{ float(texsize.width) / 4, float(texsize.height) / 4 }} },
+        uniforms::u_texsize::Value{ std::array<float, 2> {{ float(texsize.width), float(texsize.height) }} },
         uniforms::u_zoom::Value{ float(state.getZoom()) },
         uniforms::u_rotate_with_map::Value{ values.rotationAlignment == AlignmentType::Map },
         uniforms::u_texture::Value{ 0 },
diff --git a/src/mbgl/programs/symbol_program.hpp b/src/mbgl/programs/symbol_program.hpp
index 9eaa140955..809eacdd6d 100644
--- a/src/mbgl/programs/symbol_program.hpp
+++ b/src/mbgl/programs/symbol_program.hpp
@@ -67,8 +67,8 @@ struct SymbolLayoutAttributes : gl::Attributes<
                 static_cast<int16_t>(::round(o.y * 64))
             }},
             {{
-                static_cast<uint16_t>(tx / 4),
-                static_cast<uint16_t>(ty / 4),
+                tx,
+                ty,
                 mbgl::attributes::packUint8Pair(
                    static_cast<uint8_t>(labelminzoom * 10), // 1/10 zoom levels: z16 == 160
                    static_cast<uint8_t>(labelangle)
diff --git a/src/mbgl/sprite/sprite_atlas.cpp b/src/mbgl/sprite/sprite_atlas.cpp
index 0f4cde56ad..2175077c1f 100644
--- a/src/mbgl/sprite/sprite_atlas.cpp
+++ b/src/mbgl/sprite/sprite_atlas.cpp
@@ -14,6 +14,8 @@
 
 namespace mbgl {
 
+static constexpr uint32_t padding = 1;
+
 SpriteAtlasElement::SpriteAtlasElement(Rect<uint16_t> rect_,
                                        const style::Image::Impl& image,
                                        Size size_, float pixelRatio)
@@ -23,7 +25,6 @@ SpriteAtlasElement::SpriteAtlasElement(Rect<uint16_t> rect_,
       width(image.getWidth()),
       height(image.getHeight()) {
 
-    const float padding = 1;
 
     const float w = image.getWidth() * relativePixelRatio;
     const float h = image.getHeight() * relativePixelRatio;
@@ -148,17 +149,10 @@ optional<SpriteAtlasElement> SpriteAtlas::getImage(const std::string& id,
         };
     }
 
-    const uint16_t pixelWidth = std::ceil(entry.image->image.size.width / pixelRatio);
-    const uint16_t pixelHeight = std::ceil(entry.image->image.size.height / pixelRatio);
-
-    // Increase to next number divisible by 4, but at least 1.
-    // This is so we can scale down the texture coordinates and pack them
-    // into 2 bytes rather than 4 bytes.
-    const uint16_t packWidth = (pixelWidth + 1) + (4 - (pixelWidth + 1) % 4);
-    const uint16_t packHeight = (pixelHeight + 1) + (4 - (pixelHeight + 1) % 4);
+    const uint16_t width = std::ceil(entry.image->image.size.width / pixelRatio) + 2 * padding;
+    const uint16_t height = std::ceil(entry.image->image.size.height / pixelRatio) + 2 * padding;
 
-    // We have to allocate a new area in the bin, and store an empty image in it.
-    Rect<uint16_t> rect = bin.allocate(packWidth, packHeight);
+    Rect<uint16_t> rect = bin.allocate(width, height);
     if (rect.w == 0) {
         if (debug::spriteWarnings) {
             Log::Warning(Event::Sprite, "sprite atlas bitmap overflow");
@@ -187,7 +181,6 @@ void SpriteAtlas::copy(const Entry& entry, optional<Rect<uint16_t>> Entry::*entr
     const PremultipliedImage& src = entry.image->image;
     const Rect<uint16_t>& rect = *(entry.*entryRect);
 
-    const uint32_t padding = 1;
     const uint32_t x = (rect.x + padding) * pixelRatio;
     const uint32_t y = (rect.y + padding) * pixelRatio;
     const uint32_t w = src.size.width;
diff --git a/src/mbgl/text/glyph_atlas.cpp b/src/mbgl/text/glyph_atlas.cpp
index b43971f704..c6083fe0cc 100644
--- a/src/mbgl/text/glyph_atlas.cpp
+++ b/src/mbgl/text/glyph_atlas.cpp
@@ -184,14 +184,8 @@ Rect<uint16_t> GlyphAtlas::addGlyph(GlyphValue& value) {
 
     // Add a 1px border around every image.
     const uint32_t padding = 1;
-    uint16_t width = value.bitmap.size.width + 2 * padding;
-    uint16_t height = value.bitmap.size.height + 2 * padding;
-
-    // Increase to next number divisible by 4, but at least 1.
-    // This is so we can scale down the texture coordinates and pack them
-    // into 2 bytes rather than 4 bytes.
-    width += (4 - width % 4);
-    height += (4 - height % 4);
+    const uint16_t width = value.bitmap.size.width + 2 * padding;
+    const uint16_t height = value.bitmap.size.height + 2 * padding;
 
     Rect<uint16_t> rect = bin.allocate(width, height);
     if (rect.w == 0) {