Adding issue #9 Graphics Contrast

guidelines/index.html

@@ -488,6 +488,24 @@ <h4>Images of Text (No Exception)</h4>
 					<p class="change">Unchanged</p>
 					<p><a>Images of text</a> are only used for <a>pure decoration</a> or where a particular presentation of <a>text</a> is <a>essential</a> to the information being conveyed.</p>
 				</section>
+
+                        <section class="sc">
+                            <h4>Graphics Contrast</h4>
+                            <p class="conformance-level">AA</p>
+                            <p class="change">New</p>
+                            <p>The visual presentation of graphical objects that are essential for understanding the content or functionality have a contrast ratio of at least 4.5:1 against the adjacent color(s), except for the following:</p>
+                            <dl>
+                                <dt>Thicker</dt>
+                                <dd>For graphical objects with a minimum width and height of at least 3 CSS pixels, the graphic has a contrast ratio of at least 3:1.</dd>
+                                <dt>Sensory</dt>
+                                <dd>Non-text content that is primarily intended to create a visual sensory experience has no minimum contrast requirement;</dd>
+                                <dt>Logotypes</dt>
+                                <dd>Graphics that are part of a logo or brand name have no minimum contrast requirement.</dd>
+                                <dt>Essential</dt>
+                                <dd>A particular presentation of the graphical is essential to the information being conveyed.</dd>
+                            </dl>
+                        </section>
+
 			</section>
 		</section>
 
@@ -1157,6 +1175,10 @@ <h1>Glossary</h1>
 				<dd>
 					<p>any sequence where words and paragraphs are presented in an order that does not change the meaning of the content</p>
 				</dd>
+                        <dt><dfn>CSS pixels</dfn></dt>
+                        <dd>
+                              <p>A CSS pixel is the canonical unit of measure for all lengths and measurements in CSS. This unit is density-independent, and distinct from actual hardware pixels present in a display. User agents and operating systems should ensure that a CSS pixel is set as closely as possible to the <a href="https://www.w3.org/TR/css3-values/#reference-pixel">reference pixel</a>, which takes into account the physical dimensions of the display and the assumed viewing distance (factors which cannot be determined by content authors).</p>
+                        </dd>
 				<dt><dfn>emergency</dfn></dt>
 				<dd>
 					<p>a sudden, unexpected situation or occurrence that requires immediate action to preserve health, safety, or property</p>
@@ -1198,6 +1220,10 @@ <h1>Glossary</h1>
 					<p>The current working definition in the field for <strong>"pair of opposing transitions involving a saturated red"</strong> is where, for either or both states involved in each transition, R/(R+ G + B) &gt;= 0.8, and the change in the value of (R-G-B)x320 is &gt; 20 (negative values of (R-G-B)x320 are set to zero) for both transitions. R, G, B values range from 0-1 as specified in “relative luminance” definition. [[HARDING-BINNIE]]</p>
 					<p>Tools are available that will carry out analysis from video screen capture. However, no tool is necessary to evaluate for this condition if flashing is less than or equal to 3 flashes in any one second. Content automatically passes (see #1 and #2 above).</p>
 				</dd>
+                        <dt><dfn>graphical object</dfn></dt>
+                        <dd>
+                              <p>A graphic or section of a graphic that represents a distinct object or sub-component with semantic meaning. It may be a component of a larger structured graphic such as a chart or map. There is a related concept in the <a href="https://www.w3.org/TR/graphics-aria-1.0/#graphics-object">ARIA graphics module</a> for graphics with a document structure but this applies to bitmap and vector graphics, or distinct visual elements within them.</p>
+                        </dd>
 				<dt><dfn>human language</dfn></dt>
 				<dd>
 					<p>language that is spoken, written or signed (through visual or tactile means) to communicate with humans</p>