279 lines
12 KiB
JavaScript
279 lines
12 KiB
JavaScript
/**
|
|
* @fileoverview Implements the PC8080 Video component.
|
|
* @author <a href="mailto:Jeff@pcjs.org">Jeff Parsons</a>
|
|
* @version 1.0
|
|
* Created 2016-Apr-20
|
|
*
|
|
* Copyright © 2012-2016 Jeff Parsons <Jeff@pcjs.org>
|
|
*
|
|
* This file is part of PCjs, which is part of the JavaScript Machines Project (aka JSMachines)
|
|
* at <http://jsmachines.net/> and <http://pcjs.org/>.
|
|
*
|
|
* PCjs is free software: you can redistribute it and/or modify it under the terms of the
|
|
* GNU General Public License as published by the Free Software Foundation, either version 3
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* PCjs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
|
|
* even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along with PCjs. If not,
|
|
* see <http://www.gnu.org/licenses/gpl.html>.
|
|
*
|
|
* You are required to include the above copyright notice in every source code file of every
|
|
* copy or modified version of this work, and to display that copyright notice on every screen
|
|
* that loads or runs any version of this software (see Computer.COPYRIGHT).
|
|
*
|
|
* Some PCjs files also attempt to load external resource files, such as character-image files,
|
|
* ROM files, and disk image files. Those external resource files are not considered part of the
|
|
* PCjs program for purposes of the GNU General Public License, and the author does not claim
|
|
* any copyright as to their contents.
|
|
*/
|
|
|
|
"use strict";
|
|
|
|
if (NODE) {
|
|
var str = require("../../shared/lib/strlib");
|
|
var web = require("../../shared/lib/weblib");
|
|
var DumpAPI = require("../../shared/lib/dumpapi");
|
|
var Component = require("../../shared/lib/component");
|
|
var Memory = require("./memory");
|
|
var Messages = require("./messages");
|
|
var State = require("./state");
|
|
}
|
|
|
|
/**
|
|
* Video(parmsVideo, canvas, context, textarea, container)
|
|
*
|
|
* The Video component can be configured with the following (parmsVideo) properties:
|
|
*
|
|
* screenWidth: width of the screen canvas, in pixels
|
|
* screenHeight: height of the screen canvas, in pixels
|
|
* screenColor: background color of the screen canvas (default is black)
|
|
* aspectRatio
|
|
* frameBuffer
|
|
* interruptRate (eg, 120)
|
|
* refreshRate (eg, 60)
|
|
* rotation (eg, 90)
|
|
*
|
|
* @constructor
|
|
* @extends Component
|
|
* @param {Object} parmsVideo
|
|
* @param {Object} [canvas]
|
|
* @param {Object} [context]
|
|
* @param {Object} [textarea]
|
|
* @param {Object} [container]
|
|
*/
|
|
function Video(parmsVideo, canvas, context, textarea, container)
|
|
{
|
|
Component.call(this, "Video", parmsVideo, Video, Messages.VIDEO);
|
|
this.interruptRate = parmsVideo['interruptRate'];
|
|
this.refreshRate = parmsVideo['refreshRate'] || 60;
|
|
this.setReady();
|
|
}
|
|
|
|
Component.subclass(Video);
|
|
|
|
/**
|
|
* initBus(cmp, bus, cpu, dbg)
|
|
*
|
|
* @this {Video}
|
|
* @param {Computer} cmp
|
|
* @param {Bus} bus
|
|
* @param {CPUSim} cpu
|
|
* @param {Debugger} dbg
|
|
*/
|
|
Video.prototype.initBus = function(cmp, bus, cpu, dbg)
|
|
{
|
|
this.cmp = cmp;
|
|
this.bus = bus;
|
|
this.cpu = cpu;
|
|
this.dbg = dbg;
|
|
};
|
|
|
|
/**
|
|
* getRefreshRate()
|
|
*
|
|
* @this {Video}
|
|
* @return {number}
|
|
*/
|
|
Video.prototype.getRefreshRate = function()
|
|
{
|
|
return Math.max(this.refreshRate, this.interruptRate);
|
|
};
|
|
|
|
/**
|
|
* updateScreen(n)
|
|
*
|
|
* Propagates the video buffer to the cell cache and updates the screen with any changes. Forced updates
|
|
* are generally internal updates triggered by an I/O operation or other state change, while non-forced updates
|
|
* are the periodic updates coming from the CPU.
|
|
*
|
|
* For every cell in the video buffer, compare it to the cell stored in the cell cache, render if it differs,
|
|
* and then update the cell cache to match. Since initCache() sets every cell in the cell cache to an
|
|
* invalid value, we're assured that the next call to updateScreen() will redraw the entire (visible) video buffer.
|
|
*
|
|
* @this {Video}
|
|
* @param {number} n (where 0 <= n < getRefreshRate() for a normal update, or -1 for a forced update)
|
|
*/
|
|
Video.prototype.updateScreen = function(n)
|
|
{
|
|
if (!(n & 1)) {
|
|
/*
|
|
* On even updates, call cpu.requestINTR(1), and also update our copy of the screen.
|
|
*/
|
|
this.cpu.requestINTR(1);
|
|
} else {
|
|
/*
|
|
* On odd updates, call cpu.requestINTR(2), but do NOT update our copy of the screen, because
|
|
* the machine has presumably only updated the top half of the frame buffer at this point; it will
|
|
* update the bottom half of the frame buffer after acknowledging this interrupt.
|
|
*/
|
|
this.cpu.requestINTR(2);
|
|
}
|
|
};
|
|
|
|
/**
|
|
* Video.init()
|
|
*
|
|
* This function operates on every HTML element of class "video", extracting the
|
|
* JSON-encoded parameters for the Video constructor from the element's "data-value"
|
|
* attribute, invoking the constructor to create a Video component, and then binding
|
|
* any associated HTML controls to the new component.
|
|
*/
|
|
Video.init = function()
|
|
{
|
|
var aeVideo = Component.getElementsByClass(document, PCJSCLASS, "video");
|
|
for (var iVideo = 0; iVideo < aeVideo.length; iVideo++) {
|
|
var eVideo = aeVideo[iVideo];
|
|
var parmsVideo = Component.getComponentParms(eVideo);
|
|
|
|
var eCanvas = document.createElement("canvas");
|
|
if (eCanvas === undefined || !eCanvas.getContext) {
|
|
eVideo.innerHTML = "<br/>Missing <canvas> support. Please try a newer web browser.";
|
|
return;
|
|
}
|
|
|
|
eCanvas.setAttribute("class", "pcjs-canvas");
|
|
eCanvas.setAttribute("width", parmsVideo['screenWidth']);
|
|
eCanvas.setAttribute("height", parmsVideo['screenHeight']);
|
|
eCanvas.style.backgroundColor = parmsVideo['screenColor'];
|
|
|
|
/*
|
|
* The "contenteditable" attribute on a canvas element NOTICEABLY slows down canvas drawing on
|
|
* Safari as soon as you give the canvas focus (ie, click away from the canvas, and drawing speeds
|
|
* up; click on the canvas, and drawing slows down). So the "transparent textarea hack" that we
|
|
* once employed as only a work-around for Android devices is now our default.
|
|
*
|
|
* eCanvas.setAttribute("contenteditable", "true");
|
|
*
|
|
* HACK: A canvas style of "auto" provides for excellent responsive canvas scaling in EVERY browser
|
|
* except IE9/IE10, so I recalculate the appropriate CSS height every time the parent DIV is resized;
|
|
* IE11 works without this hack, so we take advantage of the fact that IE11 doesn't identify as "MSIE".
|
|
*
|
|
* The other reason it's good to keep this particular hack limited to IE9/IE10 is that most other
|
|
* browsers don't actually support an 'onresize' handler on anything but the window object.
|
|
*/
|
|
eCanvas.style.height = "auto";
|
|
if (web.getUserAgent().indexOf("MSIE") >= 0) {
|
|
eVideo.onresize = function(eParent, eChild, cx, cy) {
|
|
return function onResizeVideo() {
|
|
eChild.style.height = (((eParent.clientWidth * cy) / cx) | 0) + "px";
|
|
};
|
|
}(eVideo, eCanvas, parmsVideo['screenWidth'], parmsVideo['screenHeight']);
|
|
eVideo.onresize();
|
|
}
|
|
/*
|
|
* The following is a related hack that allows the user to force the screen to use a particular aspect
|
|
* ratio if an 'aspect' attribute or URL parameter is set. Initially, it's just for testing purposes
|
|
* until we figure out a better UI. And note that we use our web.onPageEvent() helper function to make
|
|
* sure we don't trample any other 'onresize' handler(s) attached to the window object.
|
|
*/
|
|
var aspect = +(parmsVideo['aspect'] || Component.parmsURL['aspect']);
|
|
/*
|
|
* No 'aspect' parameter yields NaN, which is falsey, and anything else must satisfy my arbitrary
|
|
* constraints of 0.3 <= aspect <= 3.33, to prevent any useless (or worse, browser-blowing) results.
|
|
*/
|
|
if (aspect && aspect >= 0.3 && aspect <= 3.33) {
|
|
web.onPageEvent('onresize', function(eParent, eChild, aspectRatio) {
|
|
return function onResizeWindow() {
|
|
/*
|
|
* Since aspectRatio is the target width/height, we have:
|
|
*
|
|
* eParent.clientWidth / eChild.style.height = aspectRatio
|
|
*
|
|
* which means that:
|
|
*
|
|
* eChild.style.height = eParent.clientWidth / aspectRatio
|
|
*
|
|
* so for example, if aspectRatio is 16:9, or 1.78, and clientWidth = 640,
|
|
* then the calculated height should approximately 360.
|
|
*/
|
|
eChild.style.height = ((eParent.clientWidth / aspectRatio)|0) + "px";
|
|
};
|
|
}(eVideo, eCanvas, aspect));
|
|
window['onresize']();
|
|
}
|
|
eVideo.appendChild(eCanvas);
|
|
|
|
/*
|
|
* HACK: Android-based browsers, like the Silk (Amazon) browser and Chrome for Android, don't honor the
|
|
* "contenteditable" attribute; that is, when the canvas receives focus, they don't activate the on-screen
|
|
* keyboard. So my fallback is to create a transparent textarea on top of the canvas.
|
|
*
|
|
* The parent DIV must have a style of "position:relative" (alternatively, a class of "pcjs-container"),
|
|
* so that we can position the textarea using absolute coordinates. Also, we don't want the textarea to be
|
|
* visible, but we must use "opacity:0" instead of "visibility:hidden", because the latter seems to prevent
|
|
* the element from receiving events. These styling requirements are taken care of in components.css
|
|
* (see references to the "pcjs-video-object" class).
|
|
*
|
|
* UPDATE: Unfortunately, Android keyboards like to compose whole words before transmitting any of the
|
|
* intervening characters; our textarea's keyDown/keyUp event handlers DO receive intervening key events,
|
|
* but their keyCode property is ZERO. Virtually the only usable key event we receive is the Enter key.
|
|
* Android users will have to use machines that include their own on-screen "soft keyboard", or use an
|
|
* external keyboard.
|
|
*
|
|
* The following attempt to use a password-enabled input field didn't work any better on Android. You could
|
|
* clearly see the overlaid semi-transparent input field, but none of the input characters were passed along,
|
|
* with the exception of the "Go" (Enter) key.
|
|
*
|
|
* var eInput = document.createElement("input");
|
|
* eInput.setAttribute("type", "password");
|
|
* eInput.setAttribute("style", "position:absolute; left:0; top:0; width:100%; height:100%; opacity:0.5");
|
|
* eVideo.appendChild(eInput);
|
|
*
|
|
* See this Chromium issue for more information: https://code.google.com/p/chromium/issues/detail?id=118639
|
|
*/
|
|
var eTextArea = document.createElement("textarea");
|
|
|
|
/*
|
|
* As noted in keyboard.js, the keyboard on an iOS device tends to pop up with the SHIFT key depressed,
|
|
* which is not the initial keyboard state that the Keyboard component expects, so hopefully turning off
|
|
* these "auto" attributes will help.
|
|
*/
|
|
if (web.isUserAgent("iOS")) {
|
|
eTextArea.setAttribute("autocapitalize", "off");
|
|
eTextArea.setAttribute("autocorrect", "off");
|
|
}
|
|
eVideo.appendChild(eTextArea);
|
|
|
|
/*
|
|
* Now we can create the Video object, record it, and wire it up to the associated document elements.
|
|
*/
|
|
var eContext = eCanvas.getContext("2d");
|
|
var video = new Video(parmsVideo, eCanvas, eContext, eTextArea /* || eInput */, eVideo);
|
|
|
|
/*
|
|
* Bind any video-specific controls (eg, the Refresh button). There are no essential controls, however;
|
|
* even the "Refresh" button is just a diagnostic tool, to ensure that the screen contents are up-to-date.
|
|
*/
|
|
Component.bindComponentControls(video, eVideo, PCJSCLASS);
|
|
}
|
|
};
|
|
|
|
/*
|
|
* Initialize every Video module on the page.
|
|
*/
|
|
web.onInit(Video.init);
|
|
|
|
if (NODE) module.exports = Video;
|