Chris@1033: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@1033: 
Chris@1033: /*
Chris@1033:     Sonic Visualiser
Chris@1033:     An audio file viewer and annotation editor.
Chris@1033:     Centre for Digital Music, Queen Mary, University of London.
Chris@1033:     
Chris@1033:     This program is free software; you can redistribute it and/or
Chris@1033:     modify it under the terms of the GNU General Public License as
Chris@1033:     published by the Free Software Foundation; either version 2 of the
Chris@1033:     License, or (at your option) any later version.  See the file
Chris@1033:     COPYING included with this distribution for more information.
Chris@1033: */
Chris@1033: 
Chris@1033: #include "ScrollableImageCache.h"
Chris@1033: 
Chris@1164: #include "base/HitCount.h"
Chris@1164: 
Chris@1033: #include <iostream>
Chris@1033: using namespace std;
Chris@1033: 
Chris@1143: //#define DEBUG_SCROLLABLE_IMAGE_CACHE 1
Chris@1033: 
Chris@1033: void
Chris@1113: ScrollableImageCache::scrollTo(const LayerGeometryProvider *v,
Chris@1113:                                sv_frame_t newStartFrame)
Chris@1033: {
Chris@1164:     static HitCount count("ScrollableImageCache: scrolling");
Chris@1164:     
Chris@1122:     int dx = (v->getXForFrame(m_startFrame) -
Chris@1266:               v->getXForFrame(newStartFrame));
Chris@1122:     
Chris@1122: #ifdef DEBUG_SCROLLABLE_IMAGE_CACHE
Chris@1122:     cerr << "ScrollableImageCache::scrollTo: start frame " << m_startFrame
Chris@1266:          << " -> " << newStartFrame << ", dx = " << dx << endl;
Chris@1122: #endif
Chris@1122: 
Chris@1079:     if (m_startFrame == newStartFrame) {
Chris@1266:         // haven't moved
Chris@1164:         count.hit();
Chris@1079:         return;
Chris@1079:     }
Chris@1266:         
Chris@1033:     m_startFrame = newStartFrame;
Chris@1266:         
Chris@1033:     if (!isValid()) {
Chris@1164:         count.miss();
Chris@1266:         return;
Chris@1033:     }
Chris@1033: 
Chris@1033:     int w = m_image.width();
Chris@1033: 
Chris@1033:     if (dx == 0) {
Chris@1266:         // haven't moved visibly (even though start frame may have changed)
Chris@1164:         count.hit();
Chris@1266:         return;
Chris@1033:     }
Chris@1033: 
Chris@1033:     if (dx <= -w || dx >= w) {
Chris@1266:         // scrolled entirely off
Chris@1266:         invalidate();
Chris@1164:         count.miss();
Chris@1266:         return;
Chris@1033:     }
Chris@1164: 
Chris@1164:     count.partial();
Chris@1266:         
Chris@1033:     // dx is in range, cache is scrollable
Chris@1033: 
Chris@1033:     int dxp = dx;
Chris@1033:     if (dxp < 0) dxp = -dxp;
Chris@1033: 
Chris@1033:     int copylen = (w - dxp) * int(sizeof(QRgb));
Chris@1033:     for (int y = 0; y < m_image.height(); ++y) {
Chris@1266:         QRgb *line = (QRgb *)m_image.scanLine(y);
Chris@1266:         if (dx < 0) {
Chris@1266:             memmove(line, line + dxp, copylen);
Chris@1266:         } else {
Chris@1266:             memmove(line + dxp, line, copylen);
Chris@1266:         }
Chris@1033:     }
Chris@1266:         
Chris@1033:     // update valid area
Chris@1033:         
Chris@1118:     int px = m_validLeft;
Chris@1118:     int pw = m_validWidth;
Chris@1266:         
Chris@1033:     px += dx;
Chris@1266:         
Chris@1033:     if (dx < 0) {
Chris@1266:         // we scrolled left
Chris@1266:         if (px < 0) {
Chris@1266:             pw += px;
Chris@1266:             px = 0;
Chris@1266:             if (pw < 0) {
Chris@1266:                 pw = 0;
Chris@1266:             }
Chris@1266:         }
Chris@1033:     } else {
Chris@1266:         // we scrolled right
Chris@1266:         if (px + pw > w) {
Chris@1266:             pw = w - px;
Chris@1266:             if (pw < 0) {
Chris@1266:                 pw = 0;
Chris@1266:             }
Chris@1266:         }
Chris@1033:     }
Chris@1033: 
Chris@1118:     m_validLeft = px;
Chris@1118:     m_validWidth = pw;
Chris@1033: }
Chris@1033: 
Chris@1033: void
Chris@1033: ScrollableImageCache::adjustToTouchValidArea(int &left, int &width,
Chris@1266:                                              bool &isLeftOfValidArea) const
Chris@1033: {
Chris@1036: #ifdef DEBUG_SCROLLABLE_IMAGE_CACHE
Chris@1036:     cerr << "ScrollableImageCache::adjustToTouchValidArea: left " << left
Chris@1036:          << ", width " << width << endl;
Chris@1118:     cerr << "ScrollableImageCache: my left " << m_validLeft
Chris@1118:          << ", width " << m_validWidth << " so right " << (m_validLeft + m_validWidth) << endl;
Chris@1036: #endif
Chris@1118:     if (left < m_validLeft) {
Chris@1266:         isLeftOfValidArea = true;
Chris@1266:         if (left + width <= m_validLeft + m_validWidth) {
Chris@1266:             width = m_validLeft - left;
Chris@1266:         }
Chris@1036: #ifdef DEBUG_SCROLLABLE_IMAGE_CACHE
Chris@1036:         cerr << "ScrollableImageCache: we're left of valid area, adjusted width to " << width << endl;
Chris@1036: #endif
Chris@1033:     } else {
Chris@1266:         isLeftOfValidArea = false;
Chris@1266:         width = left + width - (m_validLeft + m_validWidth);
Chris@1266:         left = m_validLeft + m_validWidth;
Chris@1266:         if (width < 0) width = 0;
Chris@1036: #ifdef DEBUG_SCROLLABLE_IMAGE_CACHE
Chris@1036:         cerr << "ScrollableImageCache: we're right of valid area, adjusted left to " << left << ", width to " << width << endl;
Chris@1036: #endif
Chris@1033:     }
Chris@1033: }
Chris@1033:     
Chris@1033: void
Chris@1033: ScrollableImageCache::drawImage(int left,
Chris@1266:                                 int width,
Chris@1266:                                 QImage image,
Chris@1266:                                 int imageLeft,
Chris@1266:                                 int imageWidth)
Chris@1033: {
Chris@1033:     if (image.height() != m_image.height()) {
Chris@1266:         cerr << "ScrollableImageCache::drawImage: ERROR: Supplied image height "
Chris@1266:              << image.height() << " does not match cache height "
Chris@1266:              << m_image.height() << endl;
Chris@1266:         throw std::logic_error("Image height must match cache height in ScrollableImageCache::drawImage");
Chris@1033:     }
Chris@1033:     if (left < 0 || width < 0 || left + width > m_image.width()) {
Chris@1266:         cerr << "ScrollableImageCache::drawImage: ERROR: Target area (left = "
Chris@1266:              << left << ", width = " << width << ", so right = " << left + width
Chris@1040:              << ") out of bounds for cache of width " << m_image.width() << endl;
Chris@1266:         throw std::logic_error("Target area out of bounds in ScrollableImageCache::drawImage");
Chris@1033:     }
Chris@1033:     if (imageLeft < 0 || imageWidth < 0 ||
Chris@1266:         imageLeft + imageWidth > image.width()) {
Chris@1266:         cerr << "ScrollableImageCache::drawImage: ERROR: Source area (left = "
Chris@1266:              << imageLeft << ", width = " << imageWidth << ", so right = "
Chris@1040:              << imageLeft + imageWidth << ") out of bounds for image of "
Chris@1266:              << "width " << image.width() << endl;
Chris@1266:         throw std::logic_error("Source area out of bounds in ScrollableImageCache::drawImage");
Chris@1033:     }
Chris@1266:         
Chris@1033:     QPainter painter(&m_image);
Chris@1033:     painter.drawImage(QRect(left, 0, width, m_image.height()),
Chris@1266:                       image,
Chris@1266:                       QRect(imageLeft, 0, imageWidth, image.height()));
Chris@1033:     painter.end();
Chris@1033: 
Chris@1033:     if (!isValid()) {
Chris@1266:         m_validLeft = left;
Chris@1266:         m_validWidth = width;
Chris@1266:         return;
Chris@1033:     }
Chris@1266:         
Chris@1118:     if (left < m_validLeft) {
Chris@1266:         if (left + width > m_validLeft + m_validWidth) {
Chris@1266:             // new image completely contains the old valid area --
Chris@1266:             // use the new area as is
Chris@1266:             m_validLeft = left;
Chris@1266:             m_validWidth = width;
Chris@1266:         } else if (left + width < m_validLeft) {
Chris@1266:             // new image completely off left of old valid area --
Chris@1266:             // we can't extend the valid area because the bit in
Chris@1266:             // between is not valid, so must use the new area only
Chris@1266:             m_validLeft = left;
Chris@1266:             m_validWidth = width;
Chris@1266:         } else {
Chris@1266:             // new image overlaps old valid area on left side --
Chris@1266:             // use new left edge, and extend width to existing
Chris@1266:             // right edge
Chris@1266:             m_validWidth = (m_validLeft + m_validWidth) - left;
Chris@1266:             m_validLeft = left;
Chris@1266:         }
Chris@1033:     } else {
Chris@1266:         if (left > m_validLeft + m_validWidth) {
Chris@1266:             // new image completely off right of old valid area --
Chris@1266:             // we can't extend the valid area because the bit in
Chris@1266:             // between is not valid, so must use the new area only
Chris@1266:             m_validLeft = left;
Chris@1266:             m_validWidth = width;
Chris@1266:         } else if (left + width > m_validLeft + m_validWidth) {
Chris@1266:             // new image overlaps old valid area on right side --
Chris@1266:             // use existing left edge, and extend width to new
Chris@1266:             // right edge
Chris@1266:             m_validWidth = (left + width) - m_validLeft;
Chris@1266:             // (m_validLeft unchanged)
Chris@1266:         } else {
Chris@1266:             // new image completely contained within old valid
Chris@1266:             // area -- leave the old area unchanged
Chris@1266:         }
Chris@1033:     }
Chris@1033: }
Chris@1033: