1 files changed, 191 insertions, 0 deletions
diff --git a/uv_magic_uv/lib/bglx.py b/uv_magic_uv/lib/bglx.py
new file mode 100644
index 00000000..c4dadd69
--- /dev/null
+++ b/uv_magic_uv/lib/bglx.py
@@ -0,0 +1,191 @@
+from threading import Lock
+
+import gpu
+from gpu_extras.batch import batch_for_shader
+
+GL_LINES = 0
+GL_LINE_STRIP = 1
+GL_TRIANGLES = 5
+GL_TRIANGLE_FAN = 6
+GL_QUADS = 4
+
+class InternalData:
+    __inst = None
+    __lock = Lock()
+
+    def __init__(self):
+        raise NotImplementedError("Not allowed to call constructor")
+
+    @classmethod
+    def __internal_new(cls):
+        return super().__new__(cls)
+
+    @classmethod
+    def get_instance(cls):
+        if not cls.__inst:
+            with cls.__lock:
+                if not cls.__inst:
+                    cls.__inst = cls.__internal_new()
+
+        return cls.__inst
+
+    def init(self):
+        self.clear()
+
+    def set_prim_mode(self, mode):
+        self.prim_mode = mode
+
+    def set_dims(self, dims):
+        self.dims = dims
+
+    def add_vert(self, v):
+        self.verts.append(v)
+
+    def add_tex_coord(self, uv):
+        self.tex_coords.append(uv)
+
+    def set_color(self, c):
+        self.color = c
+
+    def clear(self):
+        self.prim_mode = None
+        self.verts = []
+        self.dims = None
+        self.tex_coords = []
+
+    def get_verts(self):
+        return self.verts
+
+    def get_dims(self):
+        return self.dims
+
+    def get_prim_mode(self):
+        return self.prim_mode
+
+    def get_color(self):
+        return self.color
+
+    def get_tex_coords(self):
+        return self.tex_coords
+
+
+def glBegin(mode):
+    inst = InternalData.get_instance()
+    inst.init()
+    inst.set_prim_mode(mode)
+
+
+def glColor4f(r, g, b, a):
+    inst = InternalData.get_instance()
+    inst.set_color([r, g, b, a])
+
+
+def _get_transparency_shader():
+    vertex_shader = '''
+    uniform mat4 modelViewMatrix;
+    uniform mat4 projectionMatrix;
+    
+    in vec2 pos;
+    in vec2 texCoord;
+    out vec2 uvInterp;
+    
+    void main()
+    {
+        uvInterp = texCoord;
+        gl_Position = projectionMatrix * modelViewMatrix * vec4(pos.xy, 0.0, 1.0);
+        gl_Position.z = 1.0;
+    }
+    '''
+
+    fragment_shader = '''
+    uniform sampler2D image;
+    uniform vec4 color;
+    
+    in vec2 uvInterp;
+    out vec4 fragColor;
+    
+    void main()
+    {
+        fragColor = texture(image, uvInterp);
+        fragColor.a = color.a;
+    }
+    '''
+
+    return vertex_shader, fragment_shader
+
+
+def glEnd():
+    inst = InternalData.get_instance()
+
+    color = inst.get_color()
+    coords = inst.get_verts()
+    tex_coords = inst.get_tex_coords()
+    if inst.get_dims() == 2:
+        if len(tex_coords) == 0:
+            shader = gpu.shader.from_builtin('2D_UNIFORM_COLOR')
+        else:
+            #shader = gpu.shader.from_builtin('2D_IMAGE')
+            vert_shader, frag_shader = _get_transparency_shader()
+            shader = gpu.types.GPUShader(vert_shader, frag_shader)
+    else:
+        raise NotImplemented("get_dims() != 2")
+
+    if len(tex_coords) == 0:
+        data = {
+            "pos": coords,
+        }
+    else:
+        data = {
+            "pos": coords,
+            "texCoord": tex_coords
+        }
+
+    if inst.get_prim_mode() == GL_LINES:
+        indices = []
+        for i in range(0, len(coords), 2):
+            indices.append([i, i + 1])
+        batch = batch_for_shader(shader, 'LINES', data, indices=indices)
+
+    elif inst.get_prim_mode() == GL_LINE_STRIP:
+        batch = batch_for_shader(shader, 'LINE_STRIP', data)
+
+    elif inst.get_prim_mode() == GL_TRIANGLES:
+        indices = []
+        for i in range(0, len(coords), 3):
+            indices.append([i, i + 1, i + 2])
+        batch = batch_for_shader(shader, 'TRIS', data, indices=indices)
+
+    elif inst.get_prim_mode() == GL_TRIANGLE_FAN:
+        indices = []
+        for i in range(1, len(coords) - 1):
+            indices.append([0, i, i + 1])
+        batch = batch_for_shader(shader, 'TRIS', data, indices=indices)
+
+    elif inst.get_prim_mode() == GL_QUADS:
+        indices = []
+        for i in range(0, len(coords), 4):
+            indices.extend([[i, i + 1, i + 2], [i + 2, i + 3, i]])
+        batch = batch_for_shader(shader, 'TRIS', data, indices=indices)
+    else:
+        raise NotImplemented("get_prim_mode() != (GL_LINES|GL_TRIANGLES|GL_QUADS)")
+
+    shader.bind()
+    if len(tex_coords) != 0:
+        shader.uniform_float("modelViewMatrix", gpu.matrix.get_model_view_matrix())
+        shader.uniform_float("projectionMatrix", gpu.matrix.get_projection_matrix())
+        shader.uniform_int("image", 0)
+    shader.uniform_float("color", color)
+    batch.draw(shader)
+
+    inst.clear()
+
+
+def glVertex2f(x, y):
+    inst = InternalData.get_instance()
+    inst.add_vert([x, y])
+    inst.set_dims(2)
+
+
+def glTexCoord2f(u, v):
+    inst = InternalData.get_instance()
+    inst.add_tex_coord([u, v])