Fixed smooth lines drawn with the 'none' line join mode.

src/modules/graphics/opengl/Polyline.cpp

@@ -420,7 +420,7 @@ void Polyline::draw()
 
 	gl.useVertexAttribArrays(enabledattribs);
 
-	glVertexAttribPointer(ATTRIB_POS, 2, GL_FLOAT, GL_FALSE, 0, vertices + vertex_start);
+	glVertexAttribPointer(ATTRIB_POS, 2, GL_FLOAT, GL_FALSE, 0, vertices);
 
 	// Draw the core line and the overdraw in a single draw call. We can do this
 	// because the vertex array contains both the core line and the overdraw

src/modules/graphics/opengl/Polyline.h

@@ -30,6 +30,7 @@
 
 // C++
 #include <vector>
+#include <string.h>
 
 namespace love
 {
@@ -52,7 +53,6 @@ public:
 		, overdraw_vertex_count(0)
 		, draw_mode(mode)
 		, use_quad_indices(quadindices)
-		, vertex_start(0)
 		, overdraw_vertex_start(0)
 	{}
 	virtual ~Polyline();
@@ -97,7 +97,6 @@ protected:
 	size_t overdraw_vertex_count;
 	GLenum draw_mode;
 	bool use_quad_indices;
-	size_t vertex_start;
 	size_t overdraw_vertex_start;
 
 }; // Polyline
@@ -117,9 +116,18 @@ public:
 	void render(const float *vertices, size_t count, float halfwidth, float pixel_size, bool draw_overdraw)
 	{
 		Polyline::render(vertices, count, 2 * count - 4, halfwidth, pixel_size, draw_overdraw);
-		// discard the first two vertices. (these are redundant)
-		vertex_start = 2;
-		vertex_count -= 2;
+
+		// discard the first and last two vertices. (these are redundant)
+		for (size_t i = 0; i < vertex_count - 4; ++i)
+			this->vertices[i] = this->vertices[i+2];
+
+		// The last quad is now garbage, so zero it out to make sure it doesn't
+		// get rasterized. These vertices are in between the core line vertices
+		// and the overdraw vertices in the combined vertex array, so they still
+		// get "rendered" since we draw everything with one draw call.
+		memset(&this->vertices[vertex_count - 4], 0, sizeof(love::Vector) * 4);
+
+		vertex_count -= 4;
 	}
 
 protected: