[drape] stipple pen dynamic resource and tests

1 files changed, 91 insertions, 0 deletions

diff --git a/drape/stipple_pen_resource.cpp b/drape/stipple_pen_resource.cpp
new file mode 100644
index 0000000000..266076901d
--- /dev/null
+++ b/drape/stipple_pen_resource.cpp
@@ -0,0 +1,91 @@
+#include "stipple_pen_resource.hpp"
+
+#include "../std/numeric.hpp"
+
+namespace dp
+{
+
+uint32_t const MAX_STIPPLE_PEN_LENGTH = 254;
+uint32_t const COLUMN_WIDTH = MAX_STIPPLE_PEN_LENGTH + 1;
+
+StipplePenPacker::StipplePenPacker(m2::PointU const & canvasSize)
+  : m_canvasSize(canvasSize)
+  , m_currentColumn(0)
+{
+  // canvasSize.x - 1 = we reserve 1 pixel border on left
+  // to reduce problems with bilinear filtration on GPU
+  // MAX_STIPPLE_PEN_LENGTH + 1 = we reserve 1 pixel empty space after pen resource
+  // pen in last column reserve 1 pixel on right size of canvas
+  uint32_t columnCount = floor((canvasSize.x - 1) / MAX_STIPPLE_PEN_LENGTH);
+  m_columns.resize(columnCount, 0);
+}
+
+m2::RectU StipplePenPacker::PackResource(uint32_t width)
+{
+  ASSERT(m_currentColumn < m_columns.size(), ());
+  uint32_t countInColumn = m_columns[m_currentColumn];
+  // on one pattern we reserve 2 pixels. 1 pixel for pattern
+  // and 1 pixel for empty space beetween patterns
+  // also we reserve 1 pixel border on top of canvas
+  uint32_t yOffset = countInColumn * 2 + 1;
+  // ASSERT that ne pattern can be packed in current column
+  ASSERT(yOffset + 2 < m_canvasSize.y, ());
+  ++m_columns[m_currentColumn];
+  // 1 + m_currentColumn = reserve 1 pixel border on left side
+  uint32_t xOffset = 1 + m_currentColumn * COLUMN_WIDTH;
+  // we check if new pattern can be mapped in this column
+  // yOffset + 4 = 2 pixels on current pattern and 2 for new pattern
+  if (yOffset + 4 > m_canvasSize.y)
+    m_currentColumn++;
+
+  // maxY = yOffset + 1 because real height of stipple pattern is 1
+  return m2::RectU(xOffset, yOffset, xOffset + width, yOffset + 1);
+}
+
+StipplePenResource::StipplePenResource(StipplePenKey const & key)
+  : m_key(key)
+{
+  uint32_t fullPattern = accumulate(m_key.m_pattern.begin(), m_key.m_pattern.end(), 0);
+  ASSERT(fullPattern < MAX_STIPPLE_PEN_LENGTH, ());
+  uint32_t count = floor(MAX_STIPPLE_PEN_LENGTH / fullPattern);
+  m_pixelLength = count * fullPattern;
+}
+
+uint32_t StipplePenResource::GetSize() const
+{
+  return m_pixelLength;
+}
+
+uint32_t StipplePenResource::GetBufferSize() const
+{
+  return m_pixelLength;
+}
+
+TextureFormat StipplePenResource::GetExpectedFormat() const
+{
+  return ALPHA;
+}
+
+void StipplePenResource::Rasterize(void * buffer)
+{
+  uint8_t * pixels = static_cast<uint8_t *>(buffer);
+  uint16_t offset = 0;
+  for (size_t i = 0; i < m_key.m_pattern.size(); ++i)
+  {
+    uint8_t value = (i & 0x1) == 0 ? 255 : 0;
+    uint8_t length = m_key.m_pattern[i];
+    memset(pixels + offset, value, length * sizeof(uint8_t));
+    offset += length;
+  }
+
+  uint8_t period = offset;
+
+  while (offset < m_pixelLength)
+  {
+    memcpy(pixels + offset, pixels, period);
+    offset += period;
+  }
+}
+
+}
+