| 1 | // Copyright (c) 2013 The Chromium Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | package org.chromium.content.browser; |
| 6 | |
| 7 | /** |
| 8 | * Cached copy of all positions and scales (CSS-to-DIP-to-physical pixels) |
| 9 | * reported from the renderer. |
| 10 | * Provides wrappers and a utility class to help with coordinate transforms on the client side. |
| 11 | * Provides the internally-visible set of update methods (called from ContentViewCore). |
| 12 | * |
| 13 | * Unless stated otherwise, all coordinates are in CSS (document) coordinate space. |
| 14 | */ |
| 15 | public class RenderCoordinates { |
| 16 | // Scroll offset from the native in CSS. |
| 17 | private float mScrollXCss; |
| 18 | private float mScrollYCss; |
| 19 | |
| 20 | // Content size from native in CSS. |
| 21 | private float mContentWidthCss; |
| 22 | private float mContentHeightCss; |
| 23 | |
| 24 | // Last-frame render-reported viewport size in CSS. |
| 25 | private float mLastFrameViewportWidthCss; |
| 26 | private float mLastFrameViewportHeightCss; |
| 27 | |
| 28 | // Cached page scale factor from native. |
| 29 | private float mPageScaleFactor = 1.0f; |
| 30 | private float mMinPageScaleFactor = 1.0f; |
| 31 | private float mMaxPageScaleFactor = 1.0f; |
| 32 | |
| 33 | // Cached device density. |
| 34 | private float mDeviceScaleFactor; |
| 35 | |
| 36 | private float mContentOffsetYPix; |
| 37 | |
| 38 | // Internally-visible set of update methods (used by ContentViewCore). |
| 39 | void reset() { |
| 40 | mScrollXCss = mScrollYCss = 0; |
| 41 | mPageScaleFactor = 1.0f; |
| 42 | } |
| 43 | |
| 44 | void updateContentSizeCss(float contentWidthCss, float contentHeightCss) { |
| 45 | mContentWidthCss = contentWidthCss; |
| 46 | mContentHeightCss = contentHeightCss; |
| 47 | } |
| 48 | |
| 49 | void setDeviceScaleFactor(float deviceScaleFactor) { |
| 50 | mDeviceScaleFactor = deviceScaleFactor; |
| 51 | } |
| 52 | |
| 53 | void updateFrameInfo( |
| 54 | float scrollXCss, float scrollYCss, |
| 55 | float contentWidthCss, float contentHeightCss, |
| 56 | float viewportWidthCss, float viewportHeightCss, |
| 57 | float pageScaleFactor, float minPageScaleFactor, float maxPageScaleFactor, |
| 58 | float contentOffsetYPix) { |
| 59 | mScrollXCss = scrollXCss; |
| 60 | mScrollYCss = scrollYCss; |
| 61 | mPageScaleFactor = pageScaleFactor; |
| 62 | mMinPageScaleFactor = minPageScaleFactor; |
| 63 | mMaxPageScaleFactor = maxPageScaleFactor; |
| 64 | mContentOffsetYPix = contentOffsetYPix; |
| 65 | |
| 66 | updateContentSizeCss(contentWidthCss, contentHeightCss); |
| 67 | mLastFrameViewportWidthCss = viewportWidthCss; |
| 68 | mLastFrameViewportHeightCss = viewportHeightCss; |
| 69 | } |
| 70 | |
| 71 | /** |
| 72 | * Handles conversion of a point from window-relative-local-dip or screen-pix |
| 73 | * to document-absolute-CSS space and vice versa. |
| 74 | */ |
| 75 | public class NormalizedPoint { |
| 76 | private float mXAbsoluteCss, mYAbsoluteCss; |
| 77 | |
| 78 | private NormalizedPoint() { |
| 79 | } |
| 80 | |
| 81 | /** |
| 82 | * @return Absolute CSS (document) X coordinate of the point. |
| 83 | */ |
| 84 | public float getXAbsoluteCss() { return mXAbsoluteCss; } |
| 85 | |
| 86 | /** |
| 87 | * @return Absolute CSS (document) Y coordinate of the point. |
| 88 | */ |
| 89 | public float getYAbsoluteCss() { return mYAbsoluteCss; } |
| 90 | |
| 91 | /** |
| 92 | * @return Local device-scale-unadjusted X coordinate of the point. |
| 93 | */ |
| 94 | public float getXLocalDip() { return (mXAbsoluteCss - mScrollXCss) * mPageScaleFactor; } |
| 95 | |
| 96 | /** |
| 97 | * @return Local device-scale-unadjusted Y coordinate of the point. |
| 98 | */ |
| 99 | public float getYLocalDip() { return (mYAbsoluteCss - mScrollYCss) * mPageScaleFactor; } |
| 100 | |
| 101 | /** |
| 102 | * @return Physical (screen) X coordinate of the point. |
| 103 | */ |
| 104 | public float getXPix() { return getXLocalDip() * mDeviceScaleFactor; } |
| 105 | |
| 106 | /** |
| 107 | * @return Physical (screen) Y coordinate of the point. |
| 108 | */ |
| 109 | public float getYPix() { return getYLocalDip() * mDeviceScaleFactor + mContentOffsetYPix; } |
| 110 | |
| 111 | /** |
| 112 | * Sets the point to the given absolute CSS (document) coordinates. |
| 113 | */ |
| 114 | public void setAbsoluteCss(float xCss, float yCss) { |
| 115 | mXAbsoluteCss = xCss; |
| 116 | mYAbsoluteCss = yCss; |
| 117 | } |
| 118 | |
| 119 | /** |
| 120 | * Sets the point to the given local device-scale-unadjusted coordinates. |
| 121 | */ |
| 122 | public void setLocalDip(float xDip, float yDip) { |
| 123 | setAbsoluteCss( |
| 124 | xDip / mPageScaleFactor + mScrollXCss, |
| 125 | yDip / mPageScaleFactor + mScrollYCss); |
| 126 | } |
| 127 | |
| 128 | /** |
| 129 | * Sets the point to the given physical (screen) coordinates. |
| 130 | */ |
| 131 | public void setScreen(float xPix, float yPix) { |
| 132 | setLocalDip(xPix / mDeviceScaleFactor, yPix / mDeviceScaleFactor); |
| 133 | } |
| 134 | } |
| 135 | |
| 136 | /** |
| 137 | * @return A helper to convert a point between between absolute CSS and local DIP spaces. |
| 138 | */ |
| 139 | public NormalizedPoint createNormalizedPoint() { |
| 140 | return new NormalizedPoint(); |
| 141 | } |
| 142 | |
| 143 | /** |
| 144 | * @return Horizontal scroll offset in CSS pixels. |
| 145 | */ |
| 146 | public float getScrollX() { return mScrollXCss; } |
| 147 | |
| 148 | /** |
| 149 | * @return Vertical scroll offset in CSS pixels. |
| 150 | */ |
| 151 | public float getScrollY() { return mScrollYCss; } |
| 152 | |
| 153 | /** |
| 154 | * @return Horizontal scroll offset in physical pixels. |
| 155 | */ |
| 156 | public float getScrollXPix() { return fromLocalCssToPix(mScrollXCss); } |
| 157 | |
| 158 | /** |
| 159 | * @return Vertical scroll offset in physical pixels. |
| 160 | */ |
| 161 | public float getScrollYPix() { return fromLocalCssToPix(mScrollYCss); } |
| 162 | |
| 163 | /** |
| 164 | * @return Horizontal scroll offset in physical pixels (approx, integer). |
| 165 | */ |
| 166 | public int getScrollXPixInt() { return (int) Math.floor(getScrollXPix()); } |
| 167 | |
| 168 | /** |
| 169 | * @return Vertical scroll offset in physical pixels (approx, integer). |
| 170 | */ |
| 171 | public int getScrollYPixInt() { return (int) Math.floor(getScrollYPix()); } |
| 172 | |
| 173 | /** |
| 174 | * @return Width of the content in CSS pixels. |
| 175 | */ |
| 176 | public float getContentWidthCss() { return mContentWidthCss; } |
| 177 | |
| 178 | /** |
| 179 | * @return Height of the content in CSS pixels. |
| 180 | */ |
| 181 | public float getContentHeightCss() { return mContentHeightCss; } |
| 182 | |
| 183 | /** |
| 184 | * @return Approximate width of the content in physical pixels. |
| 185 | */ |
| 186 | public float getContentWidthPix() { return fromLocalCssToPix(mContentWidthCss); } |
| 187 | |
| 188 | /** |
| 189 | * @return Approximate height of the content in physical pixels. |
| 190 | */ |
| 191 | public float getContentHeightPix() { return fromLocalCssToPix(mContentHeightCss); } |
| 192 | |
| 193 | /** |
| 194 | * @return Approximate width of the content in physical pixels (integer). |
| 195 | */ |
| 196 | public int getContentWidthPixInt() { return (int) Math.ceil(getContentWidthPix()); } |
| 197 | |
| 198 | /** |
| 199 | * @return Approximate height of the content in physical pixels (integer). |
| 200 | */ |
| 201 | public int getContentHeightPixInt() { return (int) Math.ceil(getContentHeightPix()); } |
| 202 | |
| 203 | /** |
| 204 | * @return Render-reported width of the viewport in CSS pixels. |
| 205 | */ |
| 206 | public float getLastFrameViewportWidthCss() { return mLastFrameViewportWidthCss; } |
| 207 | |
| 208 | /** |
| 209 | * @return Render-reported height of the viewport in CSS pixels. |
| 210 | */ |
| 211 | public float getLastFrameViewportHeightCss() { return mLastFrameViewportHeightCss; } |
| 212 | |
| 213 | /** |
| 214 | * @return Render-reported width of the viewport in physical pixels (approximate). |
| 215 | */ |
| 216 | public float getLastFrameViewportWidthPix() { |
| 217 | return fromLocalCssToPix(mLastFrameViewportWidthCss); |
| 218 | } |
| 219 | |
| 220 | /** |
| 221 | * @return Render-reported height of the viewport in physical pixels (approximate). |
| 222 | */ |
| 223 | public float getLastFrameViewportHeightPix() { |
| 224 | return fromLocalCssToPix(mLastFrameViewportHeightCss); |
| 225 | } |
| 226 | |
| 227 | /** |
| 228 | * @return Render-reported width of the viewport in physical pixels (approx, integer). |
| 229 | */ |
| 230 | public int getLastFrameViewportWidthPixInt() { |
| 231 | return (int) Math.ceil(getLastFrameViewportWidthPix()); |
| 232 | } |
| 233 | |
| 234 | /** |
| 235 | * @return Render-reported height of the viewport in physical pixels (approx, integer). |
| 236 | */ |
| 237 | public int getLastFrameViewportHeightPixInt() { |
| 238 | return (int) Math.ceil(getLastFrameViewportHeightPix()); |
| 239 | } |
| 240 | |
| 241 | /** |
| 242 | * @return The Physical on-screen Y offset amount below the top controls. |
| 243 | */ |
| 244 | public float getContentOffsetYPix() { |
| 245 | return mContentOffsetYPix; |
| 246 | } |
| 247 | |
| 248 | /** |
| 249 | * @return Current page scale factor (maps CSS pixels to DIP pixels). |
| 250 | */ |
| 251 | public float getPageScaleFactor() { return mPageScaleFactor; } |
| 252 | |
| 253 | /** |
| 254 | * @return Minimum page scale factor to be used with the content. |
| 255 | */ |
| 256 | public float getMinPageScaleFactor() { return mMinPageScaleFactor; } |
| 257 | |
| 258 | /** |
| 259 | * @return Maximum page scale factor to be used with the content. |
| 260 | */ |
| 261 | public float getMaxPageScaleFactor() { return mMaxPageScaleFactor; } |
| 262 | |
| 263 | /** |
| 264 | * @return Current device scale factor (maps DIP pixels to physical pixels). |
| 265 | */ |
| 266 | public float getDeviceScaleFactor() { return mDeviceScaleFactor; } |
| 267 | |
| 268 | /** |
| 269 | * @return True if the page doesn't allow zoom-in/zoom-out. |
| 270 | */ |
| 271 | public boolean hasFixedPageScale() { return mMinPageScaleFactor == mMaxPageScaleFactor; } |
| 272 | |
| 273 | /** |
| 274 | * @return Maximum possible horizontal scroll in physical pixels. |
| 275 | */ |
| 276 | public float getMaxHorizontalScrollPix() { |
| 277 | return getContentWidthPix() - getLastFrameViewportWidthPix(); |
| 278 | } |
| 279 | |
| 280 | /** |
| 281 | * @return Maximum possible vertical scroll in physical pixels. |
| 282 | */ |
| 283 | public float getMaxVerticalScrollPix() { |
| 284 | return getContentHeightPix() - getLastFrameViewportHeightPix(); |
| 285 | } |
| 286 | |
| 287 | /** |
| 288 | * @return Maximum possible horizontal scroll in physical pixels (approx, integer). |
| 289 | */ |
| 290 | public int getMaxHorizontalScrollPixInt() { |
| 291 | return (int) Math.floor(getMaxHorizontalScrollPix()); |
| 292 | } |
| 293 | |
| 294 | /** |
| 295 | * @return Maximum possible vertical scroll in physical pixels (approx, integer). |
| 296 | */ |
| 297 | public int getMaxVerticalScrollPixInt() { |
| 298 | return (int) Math.floor(getMaxVerticalScrollPix()); |
| 299 | } |
| 300 | |
| 301 | /** |
| 302 | * @return Physical on-screen coordinate converted to local DIP. |
| 303 | */ |
| 304 | public float fromPixToDip(float pix) { |
| 305 | return pix / mDeviceScaleFactor; |
| 306 | } |
| 307 | |
| 308 | /** |
| 309 | * @return Local DIP converted to physical coordinates. |
| 310 | */ |
| 311 | public float fromDipToPix(float dip) { |
| 312 | return dip * mDeviceScaleFactor; |
| 313 | } |
| 314 | |
| 315 | /** |
| 316 | * @return Physical coordinate converted to local CSS. |
| 317 | */ |
| 318 | public float fromPixToLocalCss(float pix) { |
| 319 | return pix / (mDeviceScaleFactor * mPageScaleFactor); |
| 320 | } |
| 321 | |
| 322 | /** |
| 323 | * @return Local CSS converted to physical coordinates. |
| 324 | */ |
| 325 | public float fromLocalCssToPix(float css) { |
| 326 | return css * mPageScaleFactor * mDeviceScaleFactor; |
| 327 | } |
| 328 | } |