/* * * pSlideShow * by Nicholas Rezanof Rinard * contact: nicholas.r.rinard@dartmouth.edu * http://www.dartmouth.edu/~nrrinard/ * * Written: May, 2000 * Last Updated: September, 2001 * * This software is released under the GPL, with the hope but not the * requirement that modified/improved code would actually be sent back to me * */ //////////////////////////////////////////////////////////////////////////////// // A note about implementation: // // This JavaScript source file contains all the code necessary for any kind of// // pSlideShow. // // // // If I have done my job right then an implementor should not need // // to venture into this code file in order to implement pSS; editing the // // config file ought to be enough. // // // // A separate file contains the variable declarations and other // // needfully-edited things. // // // //////////////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////////////// // // // FUNCTION DEFINITIONS: // // pSlideShow function: constructor for a pSlideShow object // function pSlideShow( pImageNamesArray, pCurrentImageNumber, pImagePath, pNumberOfPages, pImageSlotName) { // Variables and Arrays this.pImageNamesArray = pImageNamesArray; this.pCurrentImageNumber = pCurrentImageNumber; this.pImagePath = pImagePath; this.pNumberOfPages = pNumberOfPages; this.pImageSlotName = pImageSlotName; this.pImageObjectsArray = new Array; // Methods this.initialize = initialize; this.switchImages = switchImages; // Initialization for(pTemp = 0; pTemp < this.pImageNamesArray.length; pTemp++) this.pImageObjectsArray[pTemp] = new Image(); } // initialize(): pSlideShow method: install the first image when the page is // // loaded. This is the same as "scrolling by zero". // function initialize() { this.switchImages(0); } // switchImages(): pSlideShow method: first set pCurrentImageNumber, then, for// // each image slot in the slideshow, create a new image entry in pImageArray, // // if needed, then install the new image. Lastly, update the plugins. // function switchImages(pScrollAmount) { // 1. wrap pCurrentImageNumber to a proper value. // this.pCurrentImageNumber = mod( (this.pCurrentImageNumber + pScrollAmount), this.pImageNamesArray.length); // 2. for each pPhotoSpot... ("pin" == "p image number") // for (var pin = 0; pin < this.pNumberOfPages; pin++) { // A. find the right number for the current installation // var bTempNumber = mod( (this.pCurrentImageNumber + pin), this.pImageNamesArray.length); // B. if the image isn't loaded, load it // if (!this.pImageObjectsArray[bTempNumber].src) { this.pImageObjectsArray[bTempNumber].src = this.pImagePath + this.pImageNamesArray[bTempNumber]; } // C. install the image // document[this.pImageSlotName + pin].src = this.pImageObjectsArray[bTempNumber].src; } // 3. call a function which executes implementation-specific code in the // // config file. // updatePlugins(this); } // mod(): javascript's mod function "does the wrong thing" by the definition I// // was taught. // function mod(a, b) { while (a < 0) a += b; while (a >= b) a -= b; return a; } // // ////////////////////////////////////////////////////////////////////////////////