GL|libgui|Client: Draw lines as triangle strips with custom width

The DGL shader now supports lines with any width. The automap and
crosshairs may use line widths outside the supported range of
GL_LINES, so this allows drawing with any arbitrary line width.

Setting GL line width via GLInfo was removed.

doomsday/apps/api/api_gl.h

@@ -105,11 +105,11 @@ enum {
 
 // Types.
 typedef unsigned char DGLubyte;
-typedef int DGLint;
-typedef unsigned int DGLuint;
-typedef int DGLsizei;
-typedef double DGLdouble;
-typedef unsigned int DGLenum;
+typedef int           DGLint;
+typedef unsigned int  DGLuint;
+typedef int           DGLsizei;
+typedef double        DGLdouble;
+typedef unsigned int  DGLenum;
 
 /// Texture formats.
 typedef enum dgltexformat_e {

doomsday/apps/client/net.dengine.client.pack/renderer.pack/shaders/dgl/dgl_draw.vsh

@@ -21,15 +21,17 @@
 DENG_LAYOUT_LOC(0) DENG_ATTRIB vec4 aVertex;
 DENG_LAYOUT_LOC(1) DENG_ATTRIB vec4 aColor;
 DENG_LAYOUT_LOC(2) DENG_ATTRIB vec2 aTexCoord[2];
+DENG_LAYOUT_LOC(4) DENG_ATTRIB vec2 aFragOffset;
 
+uniform vec2 uFragmentSize; // used for line width
 uniform mat4 uMvpMatrix;
 uniform mat4 uTexMatrix0;
 uniform mat4 uTexMatrix1;
 
 DENG_VAR vec4 vColor;
 DENG_VAR vec2 vTexCoord[2];
 
-vec2 transformTexCoord(const mat4 matrix, const vec2 tc) 
+vec2 transformTexCoord(const mat4 matrix, const vec2 tc)
 {
     vec4 coord = vec4(tc.s, tc.t, 0.0, 1.0);
     return (matrix * coord).xy;
@@ -38,7 +40,14 @@ vec2 transformTexCoord(const mat4 matrix, const vec2 tc)
 void main()
 {
     gl_Position = uMvpMatrix * aVertex;
-    vColor = aColor;    
+
+    if (uFragmentSize != vec2(0.0))
+    {
+        gl_Position.xy += normalize(mat2(uMvpMatrix) * aFragOffset) *
+                          uFragmentSize * gl_Position.w;
+    }
+
+    vColor = aColor;
     vTexCoord[0] = transformTexCoord(uTexMatrix0, aTexCoord[0]);
     vTexCoord[1] = transformTexCoord(uTexMatrix1, aTexCoord[1]);
 }

doomsday/apps/client/src/gl/dgl_common.cpp

@@ -702,7 +702,7 @@ dd_bool DGL_SetFloat(int name, float value)
     {
     case DGL_LINE_WIDTH:
         GL_state.currentLineWidth = value;
-        GLInfo::setLineWidth(value);
+//        GLInfo::setLineWidth(value);
         break;
 
     case DGL_POINT_SIZE: