<string><html><head/><body><p>Select rendering method according to your needs. <span style=" font-weight:600;">Software rendering</span> is much slower than hardware accelerated rendering using <span style=" font-weight:600;">OpenGL rendering</span>, but it works when OpenGL is not available at your platform. OpenGL rendering is selected as default and is recommended.</p><p>OpenGL rendering uses<span style=" font-weight:600;"> multisample antialiasing (MSAA)</span>, which provides good quality antialiasing. You can turn this feature on or off, but without antialiasing, bad quality image can occur. Samples count affect how much samples per pixel are considered to determine pixel color. It can be a value 1, 2, 4, 8, and 16. Most modern GPUs support at least value 8. Lower this value, if your GPU doesn't support the desired sample count.</p><p><span style=" font-weight:600;">Prefetch pages </span>prefetches (pre-renders) pages next to currently viewed pages, to avoid flickering during scrolling. Prefetched pages are stored in the page cache.</p><p><span style=" font-weight:600;">Multithreading strategy </span>defines how program will use CPU cores. Engine can use multiple cores. Strategy defines, how engine will use these cores. <span style=" font-weight:600;">Single thread</span> strategy uses only one CPU core for rendering page, and for some operations, they aren't parallelized, at the cost of more time needed for operation to be finished. But still, each page will use its own thread to be compiled/drawn. On the other side, there are two multithreading strategies, former is load balanced, latter uses maximum threads. Load balanced strategy tries to optimize number of threads to fit CPU cores, while maximum threads strategy will spawn as much threads as possible to process operations, which can be sometimes unoptimal.</p></body></html></string>
<string><html><head/><body><p>Rendering settings defines, how rendering engine should handle the page content, and appearance of displayed graphics. <span style=" font-weight:600;">Antialiasing</span> turns on antialiasing of painted shapes, such as rectangles, vector graphics, lines, but it did not affects text (characters printed on the screen). <span style=" font-weight:600;">Text antialiasing </span>turns on antialiasing of painted characters on the screen, but not any other items. Both <span style=" font-weight:600;">Antialiasing </span>and <span style=" font-weight:600;">Text antialiasing </span>affects only software renderer. If you are using hardware rendering engine, such as OpenGL rendering engine, this doesn't do anything, because OpenGL engine renders the pictures using MSAA antialiasing (if turned on).</p><p><span style=" font-weight:600;">Smooth pictures</span> transforms pictures to device space coordinates using smooth image transformation, which usually leads to better image quality. When this is turned off, then default fast transformation is used, and quality of the image is lower, if the source DPI and device DPI is different.</p><p><span style=" font-weight:600;">Ignore optional content </span>ignores all optional content settings and paints everything in the content stream. <span style=" font-weight:600;">Clip to crop box</span> clips the drawing rectangle to the crop box of the page, which is usually smaller, than whole page. The graphics outside of the crop box is not drawn (for example, it can contain marks for printer etc.). <span style=" font-weight:600;">Display page compile/draw time </span>is used mainly for debugging purposes, it displays page compile time (compiled page is stored in the cache) and draw time (when the renderer draws compiled page contents to the output device).</p></body></html></string>
<string><html><head/><body><p>Shading is meshed according the mesh quality criteria. It involves <span style=" font-weight:600;">color tolerance</span> and shape tolerance. If color of vertices of triangle in the mesh is too different (it differs more than color tolerance) then mesh is refined and triangle is subdivided. Some shadings are defined by patterns (such as <span style=" font-style:italic;">Coons patch shading </span>or <span style=" font-style:italic;">Tensor product patch shading</span>), which is also considered in meshing.</p><p><span style=" font-weight:600;">Preferred mesh resolution ratio</span> should be set to optimal balance between performance of mesh generation and quality of the mesh. Optimal triangle size will be computed in the following way: total meshing area (typically a page) will be multiplied with this ratio and that will determine the triangle size. So, if we have A4 page (210 mm x 297mm), and ratio is set to 0,01, then we will get optimal triangle size as 297 * 0.01 = ~3mm.</p><p><span style=" font-weight:600;">Minimal mesh resolution ratio</span> is ratio, which will determine triangle minimal size. At this bound, no triangles are subdivided, even if color is different or shape is not good. This should be set to a value, at which user barely can recognize patterns on the screen (for example, the size of triangle should be &lt; 1mm). But it also affect performance, because too much triangles can be generated.</p><p><span style=" font-weight:600;">Color tolerance</span> is threshold, at which is two colors recognized as different. The comparation is done component-wise, so if at least one of color components is greater than this parameter, then colors are treated as different.</p></body></html></string>
<string><html><head/><body><p>Rendering engine first compiles page for fast drawing, and then stores them in the cache. Stored compiled pages are usually drawn much faster than direct drawing. <span style=" font-weight:600;">Compiled page cache size</span> sets limits for compiled pages in kB. This limit should be at least two times large than largest compiled page size. If compiled page can't be inserted, then error is displayed during rendering. The higher this value is set, the faster the engine will be, at the cost of consumed operating memory.</p><p>Also, there is cache for thumbnails images. <span style=" font-weight:600;">Thumbnail image cache size </span>determines, how much space there is for thumbnail images. Set this value to at least fill space for thumbnails images on the screen. Again, the higher value is, the faster displaying of thumbnails is, at the cost of consumed operating memory. Thumbnails are stored as bitmaps for fast drawing, not as precompiled pages.</p><p>During rendering, fonts are cached. There is a two-level cache, one for general fonts, one for instanced fonts (fonts with given size). The <span style=" font-weight:600;">cached font limit</span> sets font cache limit (number of fonts) which can be stored in the cache. The <span style=" font-weight:600;">instanced font cache limit</span> sets font cache limit for instanced fonts (number of fonts with determined size), which can be stored in the cache. When cache limit is exceeded, then fonts are erased from the cache, but only if no operation in another thread is performed (for example, compiling pages), to avoid race conditions.</p></body></html></string>
<string><html><head/><body><p><span style=" font-weight:600;">Color management system </span>manages input and output color profiles and color transformations. It enables to perceive real colors defined in PDF document. Select 'Generic' to disable this functionality for fast color transform. <span style=" font-weight:600;">Rendering intent</span> affects how colors are transformed. Rendering intents are usually defined in content streams in PDF document, but you can override them, if you select other intent, than 'Auto'. <span style=" font-weight:600;">Accuracy </span>affects how precise the color transformation would be, at the cost of more memory consumption. <span style=" font-weight:600;">Black point compensation</span> compensates black colors out of gamut. <span style=" font-weight:600;">White paper color transformed </span>affects color of the underlying white paper - it transforms pure white from device RGB profile to output profile, if enabled.</p><p><span style=" font-weight:600;">Output color profile</span> defines output (target) rendering profile. This profile should be color space, in which your screen is displaying colors. You can also define color spaces for <span style=" font-weight:600;">gray/RGB/CMYK</span> device color spaces, which are used to transform gray/RGB/CMYK colors to the output color profile.</p></body></html></string>
<string><html><head/><body><p>If launch of application is allowed, then, after <span style=" font-weight:600;">Launch</span> action is triggered, message box appears, which asks the user, if he wants to execute external application. If user confirms the dialog, then external application is executed (for example, by windows function <span style=" font-weight:600;">ShellExecute</span>). When this option is turned off, then no dialog appears and external application is never executed.</p><p>If <span style=" font-weight:600;">URI link </span>launch is allowed, then, again, message box appears and asks the user, if he wants to open the URI link. If user confirms the dialog, then URI link is opened by standard web browser (or standard application, if URI links to the file system).</p><p>User should be really carefull with these settings, and only confirm the execution, if the document is safe, i.e. it comes from reliable source. Launching external applications and following URI links can be harmfull to the user's computer.</p></body></html></string>
<string><html><head/><body><p>Maximum count of recent files controls, how much of recent files will be displayed in menu. When document is opened, then document is addet to the top of recent file list, and recent file list is truncated from bottom, if number of recent files is greater, than maximum.</p></body></html></string>
