[cairo-commit] talks/ddc_2005 cairo.xml,1.2,1.3

[Carl Worth]

Committed by: cworth

Update of /cvs/cairo/talks/ddc_2005
In directory gabe:/tmp/cvs-serv30246

Modified Files:
	cairo.xml 
Log Message:
Stroking section is all done.

Index: cairo.xml
===================================================================
RCS file: /cvs/cairo/talks/ddc_2005/cairo.xml,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -d -r1.2 -r1.3
--- cairo.xml	19 Jul 2005 12:33:03 -0000	1.2
+++ cairo.xml	19 Jul 2005 17:07:59 -0000	1.3
@@ -6,7 +6,7 @@
     >
 
   <slides theme="cairo"
-	  presentation="an insider's guide to cairo" 
+	  presentation="an insider’s guide to cairo" 
 	  presentation-subtitle="an insider’s guide"
 	  URL="http://cairographics.org"
 	  bullet="bullet">
@@ -31,20 +31,349 @@
       <img src="rendering-model.svg" x="0" y="0" />
     </slide>
 
-    <slide title="through the scarab's belly">
+    <slide title="through the scarab’s belly">
+      <lc></lc>
       <li>stroking</li>
       <li>tessellation</li>
       <li>rasterization</li>
       <li>compositing</li>
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(250,0)" font-size="40">
+	<path d="M50,350 C 2,-189 279,581 173,49"/>
+	<text x="240" y="212" text-anchor="middle">+</text>
+	<circle fill="black" stroke="none" cx="300" cy="200" r="20"/>
+	<text x="370" y="212" text-anchor="middle">=</text>
+	<path stroke-linecap="round" stroke-width="40" d="M450,350 C 402,-189 679,581 573,49"/>
+      </g>
     </slide>
 
     <slide title="stroking">
       <g stroke="black" stroke-width="2" fill="none" transform="translate(100,0)" font-size="40">
-	<path d="M50,350 C 50,50 150,350 150,50"/>
-	<text x="210" y="212" text-anchor="middle">+</text>
-	<circle fill="black" stroke="none" cx="300" cy="200" r="20"/>
-	<text x="390" y="212" text-anchor="middle">=</text>
-	<path stroke-linecap="round" stroke-width="40" d="M450,350 C 450,50 550,350 550,50"/>
+	<path d="M50,350 C 2,-189 279,581 173,49"/>
+	<text x="240" y="212" text-anchor="middle">+</text>
+	<circle cx="300" cy="200" r="20"/>
+	<text x="370" y="212" text-anchor="middle">=</text>
+	<!-- To bad we don't can't stroke the stroke of the path here.
+		<path stroke-linecap="round" stroke-width="40" d="M450,350 C 402,-189 679,581 573,49" stroke-opacity="0.5"/>
+	     So we fake it (thanks to keithp and twin).
+	-->
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+	L 430.384294391935391, 353.901806440322565
+	L 430.096305466556062, 351.960342806591212
+"/>
       </g>
     </slide>
 
@@ -60,7 +389,7 @@
       <li>cairo doesn’t always get it right</li>
     </slide>
 
-    <slide title="cubic Bezier splines">
+    <slide title="cubic Bézier splines">
       <ul>
 	<li>well understood primitive</li>
 	<li>many pleasing properties:</li>
@@ -140,7 +469,7 @@
       </g>
     </slide>
 
-    <slide title="4) two sub-splines fell out">
+    <slide title="4) two sub-splines fall out">
       <g transform="translate(0,100)" fill="#808080">
 	<path stroke="#808080" stroke-width="2" fill="none"
 	      d="M0,300 L 200,0 L 500,0, L 800,200"/>
@@ -165,91 +494,174 @@
       </g>
     </slide>
 
-    <slide title="let's try stroking">
+    <slide title="let’s try stroking">
     </slide>
 
-    <slide title="let's try stroking">
-      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,0)" font-size="40">
-	<path d="M50,350 C 50,50 150,350 150,50"/>
+    <slide title="let’s try stroking">
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,40)" font-size="40">
+	<path d="M50,350 C 2,-189 279,581 173,49"/>
       </g>
     </slide>
 
-    <slide title="let's try stroking">
-      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,0)" font-size="40">
-	<path d="M50,350 C 50,50 150,350 150,50"/>
+    <slide title="let’s try stroking">
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,40)" font-size="40">
+	<path d="M50,350 C 2,-189 279,581 173,49"/>
 	<circle cx="50" cy="350" r="20"/>
       </g>
     </slide>
 
     <slide title="now simplify the pen">
-      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,0)" font-size="40">
-	<path d="M50,350 C 50,50 150,350 150,50"/>
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,40)" font-size="40">
+	<path d="M50,350 C 2,-189 279,581 173,49"/>
 	<path d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
 	<circle cx="70" cy="350" r="2" stroke="none" fill="red" />
 	<circle cx="60" cy="367.320508075688772" r="2" stroke="none" fill="orange" />
 	<circle cx="40" cy="367.320508075688772" r="2" stroke="none" fill="yellow" />
 	<circle cx="30" cy="350" r="2" stroke="none" fill="green" />
-	<circle cx="40" cy="332.679491924311227" r="2" stroke="orange" fill="blue" />
+	<circle cx="40" cy="332.679491924311227" r="2" stroke="none" fill="blue" />
 	<circle cx="60" cy="332.679491924311227" r="2" stroke="none" fill="violet" />
       </g>
     </slide>
 
     <slide title="ooh, pretty colors">
-      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,0)" font-size="40">
-	<path stroke="#C0C0C0" d="M50,350 C 50,50 150,350 150,50"/>
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,40)" font-size="40">
+	<path stroke="#C0C0C0" d="M50,350 C 2,-189 279,581 173,49"/>
 	<path d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
 	<circle cx="70" cy="350" r="2" stroke="none" fill="red" />
 	<circle cx="60" cy="367.320508075688772" r="2" stroke="none" fill="orange" />
 	<circle cx="40" cy="367.320508075688772" r="2" stroke="none" fill="yellow" />
 	<circle cx="30" cy="350" r="2" stroke="none" fill="green" />
-	<circle cx="40" cy="332.679491924311227" r="2" stroke="orange" fill="blue" />
+	<circle cx="40" cy="332.679491924311227" r="2" stroke="none" fill="blue" />
 	<circle cx="60" cy="332.679491924311227" r="2" stroke="none" fill="violet" />
-	<path stroke="red" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="red" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(20,0)" />
-	<path stroke="orange" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="orange" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(10, 17.320508075688772)" />
-	<path stroke="yellow" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="yellow" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(-9.999999999999999, 17.320508075688772)"/>
-	<path stroke="green" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="green" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(-19.999999999999999, 5.527147875260444e-75)"/>
-	<path stroke="blue" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="blue" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(-10, -17.320508075688772)"/>
-	<path stroke="violet" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="violet" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(9.999999999999999, -17.320508075688772)"/>
       </g>
     </slide>
 
     <slide title="...but ugly lumps">
-      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,0)" font-size="40">
-	<path stroke="#C0C0C0" d="M50,350 C 50,50 150,350 150,50"/>
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,40)" font-size="40">
+	<path stroke="#C0C0C0" d="M50,350 C 2,-189 279,581 173,49"/>
 	<path d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
 	<circle cx="70" cy="350" r="2" stroke="none" fill="red" />
 	<circle cx="60" cy="367.320508075688772" r="2" stroke="none" fill="orange" />
 	<circle cx="40" cy="367.320508075688772" r="2" stroke="none" fill="yellow" />
 	<circle cx="30" cy="350" r="2" stroke="none" fill="green" />
-	<circle cx="40" cy="332.679491924311227" r="2" stroke="orange" fill="blue" />
+	<circle cx="40" cy="332.679491924311227" r="2" stroke="none" fill="blue" />
 	<circle cx="60" cy="332.679491924311227" r="2" stroke="none" fill="violet" />
-	<path stroke="red" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="red" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(20,0)" />
-	<path stroke="orange" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="orange" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(10, 17.320508075688772)" />
-	<path stroke="yellow" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="yellow" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(-9.999999999999999, 17.320508075688772)"/>
-	<path stroke="green" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="green" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(-19.999999999999999, 5.527147875260444e-75)"/>
-	<path stroke="blue" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="blue" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(-10, -17.320508075688772)"/>
-	<path stroke="violet" d="M50,350 C 50,50 150,350 150,50"
+	<path stroke="violet" d="M50,350 C 2,-189 279,581 173,49"
 	      transform="translate(9.999999999999999, -17.320508075688772)"/>
 
 	<circle stroke="black" stroke-width="2" fill="none"
-	  cx="53" cy="210" r="16" />
+	  cx="63" cy="140" r="30" />
 	<circle stroke="black" stroke-width="2" fill="none"
-	  cx="148" cy="190" r="16" />
+	  cx="192" cy="246" r="30" />
       </g>
     </slide>
 
-    <!-- Minkowksi sum, convolution of polygonal tracings -->
+    <slide title="approximate the spline first">
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,40)" font-size="40">
+	<path stroke="black" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"/>
+	<path d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
+	<circle cx="70" cy="350" r="2" stroke="none" fill="red" />
+	<circle cx="60" cy="367.320508075688772" r="2" stroke="none" fill="orange" />
+	<circle cx="40" cy="367.320508075688772" r="2" stroke="none" fill="yellow" />
+	<circle cx="30" cy="350" r="2" stroke="none" fill="green" />
+	<circle cx="40" cy="332.679491924311227" r="2" stroke="none" fill="blue" />
+	<circle cx="60" cy="332.679491924311227" r="2" stroke="none" fill="violet" />
+      </g>
+    </slide>
+
+    <slide title="is this progress?">
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,40)" font-size="40">
+	<path stroke="#808080" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"/>
+	<path d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
+	<circle cx="70" cy="350" r="2" stroke="none" fill="red" />
+	<circle cx="60" cy="367.320508075688772" r="2" stroke="none" fill="orange" />
+	<circle cx="40" cy="367.320508075688772" r="2" stroke="none" fill="yellow" />
+	<circle cx="30" cy="350" r="2" stroke="none" fill="green" />
+	<circle cx="40" cy="332.679491924311227" r="2" stroke="none" fill="blue" />
+	<circle cx="60" cy="332.679491924311227" r="2" stroke="none" fill="violet" />
+	<path stroke="red" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(20,0)" />
+	<path stroke="orange" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(10, 17.320508075688772)" />
+	<path stroke="yellow" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(-9.999999999999999, 17.320508075688772)"/>
+	<path stroke="green" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(-19.999999999999999, 5.527147875260444e-75)"/>
+	<path stroke="blue" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(-10, -17.320508075688772)"/>
+	<path stroke="violet" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(9.999999999999999, -17.320508075688772)"/>
+      </g>
+    </slide>
+
+    <slide title="cleaning up...">
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,40)" font-size="40">
+	<path stroke="#808080" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"/>
+	<path d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
+	<circle cx="70" cy="350" r="2" stroke="none" fill="red" />
+	<circle cx="60" cy="367.320508075688772" r="2" stroke="none" fill="orange" />
+	<circle cx="40" cy="367.320508075688772" r="2" stroke="none" fill="yellow" />
+	<circle cx="30" cy="350" r="2" stroke="none" fill="green" />
+	<circle cx="40" cy="332.679491924311227" r="2" stroke="none" fill="blue" />
+	<circle cx="60" cy="332.679491924311227" r="2" stroke="none" fill="violet" />
+	<path stroke="red" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 M 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(20,0)" />
+	<path stroke="yellow" d="M 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875"
+	      transform="translate(-9.999999999999999, 17.320508075688772)"/>
+	<path stroke="green" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 M 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(-19.999999999999999, 5.527147875260444e-75)"/>
+	<path stroke="violet" d="M 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875"
+	      transform="translate(9.999999999999999, -17.320508075688772)"/>
+      </g>
+    </slide>
+
+    <slide title="...and add the pen">
+      <g stroke="black" stroke-width="2" fill="none" transform="translate(300,40)" font-size="40">
+	<path stroke="#808080" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"/>
+	<path d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
+	<circle cx="70" cy="350" r="2" stroke="none" fill="red" />
+	<circle cx="60" cy="367.320508075688772" r="2" stroke="none" fill="orange" />
+	<circle cx="40" cy="367.320508075688772" r="2" stroke="none" fill="yellow" />
+	<circle cx="30" cy="350" r="2" stroke="none" fill="green" />
+	<circle cx="40" cy="332.679491924311227" r="2" stroke="none" fill="blue" />
+	<circle cx="60" cy="332.679491924311227" r="2" stroke="none" fill="violet" />
+	<path stroke="red" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 M 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(20,0)" />
+	<path stroke="yellow" d="M 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875"
+	      transform="translate(-9.999999999999999, 17.320508075688772)"/>
+	<path stroke="green" d="M50.000000, 350.000000 L 45.851562, 204.134766 L 63.875000, 150.390625 M 191.750000, 244.671875 L 196.179688, 192.568359 L 173.000000, 49.000000"
+	      transform="translate(-19.999999999999999, 5.527147875260444e-75)"/>
+	<path stroke="violet" d="M 63.875000, 150.390625 L 95.773438, 158.169922 L 133.250000, 196.875000 L 168.007812, 235.908203 L 191.750000, 244.671875"
+	      transform="translate(9.999999999999999, -17.320508075688772)"/>
+	<path transform="translate(13.875,-199.609375)" d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
+	<path transform="translate(141.75,-105.328125)" d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
+	<path transform="translate(123,-301)" d="M70,350 L 60,367.320508075688772 L 40,367.320508075688772 L 30,350 L 40,332.679491924311227 L 60,332.679491924311227 z" />
+      </g>
+    </slide>
+
+    <!-- convolution of polygonal tracings -->
 
     <slide title="tessellation">
     </slide>