void
RasterRenderer::GenerateUnshadedImage(unsigned height_scale,
const unsigned contour_height_scale)
{
const short *src = height_matrix.GetData();
const BGRColor *oColorBuf = color_table + 64 * 256;
BGRColor *dest = image->GetTopRow();
for (unsigned y = height_matrix.GetHeight(); y > 0; --y) {
BGRColor *p = dest;
dest = image->GetNextRow(dest);
unsigned contour_row_base = ContourInterval(*src,
contour_height_scale);
unsigned char *contour_this_column_base = contour_column_base;
for (unsigned x = height_matrix.GetWidth(); x > 0; --x) {
int h = *src++;
if (gcc_likely(!RasterBuffer::IsSpecial(h))) {
if (h < 0)
h = 0;
const unsigned contour_interval =
ContourInterval(h, contour_height_scale);
h = std::min(254, h >> height_scale);
if (gcc_unlikely((contour_interval != contour_row_base)
|| (contour_interval != *contour_this_column_base))) {
*p++ = oColorBuf[h-64*256];
*contour_this_column_base = contour_row_base = contour_interval;
} else {
*p++ = oColorBuf[h];
}
} else if (RasterBuffer::IsWater(h)) {
// we're in the water, so look up the color for water
*p++ = oColorBuf[255];
} else {
/* outside the terrain file bounds: white background */
*p++ = BGRColor(0xff, 0xff, 0xff);
}
contour_this_column_base++;
}
}
gcc_const
static unsigned
ContourInterval(const TerrainHeight h, const unsigned contour_height_scale)
{
if (gcc_unlikely(h.IsSpecial()) || h.GetValue() <= 0)
return 0;
return ContourInterval(h.GetValue(), contour_height_scale);
}
