added some very basic im2d stuff to gl3

src/gl/shaders/Makefile

@@ -1,4 +1,12 @@
-all: simple_gl3.inc matfx_gl3.inc skin_gl3.inc
+all: im2d_gl3.inc simple_gl3.inc matfx_gl3.inc skin_gl3.inc
+
+im2d_gl3.inc: im2d.frag im2d.vert
+	(echo 'const char *im2d_vert_src =';\
+	 sed 's/..*/"&\\n"/' im2d.vert;\
+	 echo ';';\
+	 echo 'const char *im2d_frag_src =';\
+	 sed 's/..*/"&\\n"/' im2d.frag;\
+	 echo ';') >im2d_gl3.inc
 
 simple_gl3.inc: simple.frag simple.vert
 	(echo 'const char *simple_vert_src =';\

src/gl/shaders/im2d.frag

@@ -0,0 +1,15 @@
+#version 330
+
+uniform sampler2D tex;
+
+in vec4 v_color;
+in vec2 v_tex0;
+
+out vec4 color;
+
+void
+main(void)
+{
+	color = v_color*texture2D(tex, vec2(v_tex0.x, v_tex0.y));
+}
+

src/gl/shaders/im2d.vert

@@ -0,0 +1,23 @@
+#version 330
+
+layout(std140) uniform Im2DState
+{
+	int   u_alphaTest;
+	float u_alphaRef;
+	mat4  u_xform;
+};
+
+layout(location = 0) in vec3 in_pos;
+layout(location = 2) in vec4 in_color;
+layout(location = 3) in vec2 in_tex0;
+
+out vec4 v_color;
+out vec2 v_tex0;
+
+void
+main(void)
+{
+	gl_Position = vec4(in_pos, 1.0);
+	v_color = in_color;
+	v_tex0 = in_tex0;
+}

src/gl/shaders/im2d_gl3.inc

@@ -0,0 +1,42 @@
+const char *im2d_vert_src =
+"#version 330\n"
+
+"layout(std140) uniform Im2DState\n"
+"{\n"
+"	int   u_alphaTest;\n"
+"	float u_alphaRef;\n"
+"	mat4  u_xform;\n"
+"};\n"
+
+"layout(location = 0) in vec3 in_pos;\n"
+"layout(location = 2) in vec4 in_color;\n"
+"layout(location = 3) in vec2 in_tex0;\n"
+
+"out vec4 v_color;\n"
+"out vec2 v_tex0;\n"
+
+"void\n"
+"main(void)\n"
+"{\n"
+"	gl_Position = vec4(in_pos, 1.0);\n"
+"	v_color = in_color;\n"
+"	v_tex0 = in_tex0;\n"
+"}\n"
+;
+const char *im2d_frag_src =
+"#version 330\n"
+
+"uniform sampler2D tex;\n"
+
+"in vec4 v_color;\n"
+"in vec2 v_tex0;\n"
+
+"out vec4 color;\n"
+
+"void\n"
+"main(void)\n"
+"{\n"
+"	color = v_color*texture2D(tex, vec2(v_tex0.x, v_tex0.y));\n"
+"}\n"
+
+;