Adding task data for transform feedback

src/Renderer/Context.hpp

@@ -51,6 +51,8 @@ namespace sw
 
 	enum DrawType : unsigned int
 	{
+		// These types must stay ordered by vertices per primitive. Also, if these basic types
+		// are modified, verify the value assigned to task->verticesPerPrimitive in Renderer.cpp
 		DRAW_POINTLIST     = 0x00,
 		DRAW_LINELIST      = 0x01,
 		DRAW_LINESTRIP     = 0x02,

src/Renderer/Renderer.cpp

@@ -1457,7 +1457,12 @@ namespace sw
 			return;
 		}
 
-		task->vertexCount = triangleCount * 3;
+		task->vertexStart = start * 3;
+		task->vertexCount = triangleCount * 3;
+		// Note: Quads aren't handled for verticesPerPrimitive, but verticesPerPrimitive is used for transform feedback,
+		//       which is an OpenGL ES 3.0 feature, and OpenGL ES 3.0 doesn't support quads as a primitive type.
+		DrawType type = static_cast<DrawType>(static_cast<unsigned int>(draw->drawType) & 0xF);
+		task->verticesPerPrimitive = 1 + (type >= DRAW_LINELIST) + (type >= DRAW_TRIANGLELIST);
 		vertexRoutine(&triangle->v0, (unsigned int*)&batch, task, data);
 	}
 

src/Renderer/VertexProcessor.hpp

@@ -32,7 +32,9 @@ namespace sw
 
 	struct VertexTask
 	{
+		unsigned int vertexStart;
 		unsigned int vertexCount;
+		unsigned int verticesPerPrimitive;
 		VertexCache vertexCache;
 	};