X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=blobdiff_plain;f=source%2Fbuilders%2Fcylinder.cpp;fp=source%2Fbuilders%2Fcylinder.cpp;h=901a0f4b43cf057872a752960e30678a2a980b24;hp=0000000000000000000000000000000000000000;hb=7aaec9a70b8d7733429bec043f8e33e02956f266;hpb=bec07999d95b76f4b47cffcc564d0cd0afc0435e

diff --git a/source/builders/cylinder.cpp b/source/builders/cylinder.cpp
new file mode 100644
index 00000000..901a0f4b
--- /dev/null
+++ b/source/builders/cylinder.cpp
@@ -0,0 +1,86 @@
+#define _USE_MATH_DEFINES
+#include <cmath>
+#include "cylinder.h"
+#include "primitivebuilder.h"
+
+using namespace std;
+
+namespace Msp {
+namespace GL {
+
+CylinderBuilder::CylinderBuilder(float r, float l, unsigned s):
+	radius(r),
+	length(l),
+	segments(s)
+{
+	if(segments<3)
+		segments = 3;
+}
+
+void CylinderBuilder::build(PrimitiveBuilder &builder) const
+{
+	if(generate_tbn)
+		builder.binormal(0, 1, 0);
+	for(unsigned i=0; i<2; ++i)
+	{
+		float z = (i-0.5)*length;
+		builder.normal(0, 0, i*2.0-1.0);
+		builder.texcoord(0.5, 0.5);
+		if(generate_tbn)
+			builder.tangent((i ? 1 : -1), 0, 0);
+		builder.vertex(0, 0, z);
+		for(unsigned j=0; j<segments; ++j)
+		{
+			float a = j*M_PI*2/segments;
+			float c = cos(a);
+			float s = sin(a);
+			builder.texcoord(0.5+(i ? 0.5 : -0.5)*c, 0.5+0.5*s);
+			builder.vertex(radius*c, radius*s, z);
+		}
+	}
+
+	float u_scale = 1.0/segments;
+	float v_scale = 1;
+	adjust_texture_scale(u_scale, v_scale, radius*M_PI*2, length);
+
+	if(generate_tbn)
+		builder.binormal(0, 0, 1);
+	for(unsigned i=0; i<2; ++i)
+	{
+		float z = (i-0.5)*length;
+		for(unsigned j=0; j<=segments; ++j)
+		{
+			float a = j*M_PI*2/segments;
+			float c = cos(a);
+			float s = sin(a);
+			builder.normal(c, s, 0);
+			builder.texcoord(j*u_scale, i*v_scale);
+			if(generate_tbn)
+				builder.tangent(-s, c, 0);
+			builder.vertex(radius*c, radius*s, z);
+		}
+	}
+
+	unsigned base = 0;
+	for(unsigned i=0; i<2; ++i)
+	{
+		builder.begin(TRIANGLE_FAN);
+		builder.element(base);
+		for(unsigned j=0; j<=segments; ++j)
+			builder.element(base+1+j%segments);
+		builder.end();
+
+		base += segments+1;
+	}
+
+	builder.begin(TRIANGLE_STRIP);
+	for(unsigned j=0; j<=segments; ++j)
+	{
+		builder.element(base+segments+1+j);
+		builder.element(base+j);
+	}
+	builder.end();
+}
+
+} // namespace GL
+} // namespace Msp