Python OpenGL.GL.glBlendFunc() Examples

def _drawToolMarkers(self):
        x, y, z = self.editor.level.playerSpawnPosition()
        
        GL.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA);
        GL.glEnable(GL.GL_BLEND);
        
        color = config.selectionColors.black.get() + (0.35,)
        GL.glColor(*color)
        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_LINE)
        GL.glLineWidth(2.0)
        drawCube(FloatBox((x, y, z), (1, 1, 1)))
        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_FILL)
        drawCube(FloatBox((x, y, z), (1, 1, 1)))
        GL.glDisable(GL.GL_BLEND)
        
        GL.glEnable(GL.GL_DEPTH_TEST)
        GL.glColor(1.0, 1.0, 1.0, 1.0)
        self.drawCage(x, y, z)
        self.drawCharacterHead(x + 0.5, y + 0.5 + 0.125 * numpy.sin(self.editor.frames * 0.05), z + 0.5)
        GL.glDisable(GL.GL_DEPTH_TEST) 

def initializeGL(self):
        """Initialize OpenGL, VBOs, upload data on the GPU, etc."""

        # First check for supported GL version
        gl_version = float(gl.glGetString(gl.GL_VERSION)[:3])
        if gl_version < 3.3:
            return

        # background color
        gl.glClearColor(0, 0, 0, 0)
        gl.glEnable(gl.GL_BLEND)
        gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)

        # self.mcp_data       = mcpUBO()
        self.globaldata     = ndUBO()
        self.mcp_col_shader = BlueSkyProgram('mcp.vert', 'color.frag')
        self.mcp_tex_shader = BlueSkyProgram('mcp.vert', 'texture.frag')
        self.mcp_txt_shader = BlueSkyProgram('mcp_text.vert', 'mcp_text.frag')

        self.color_shader   = BlueSkyProgram('normal.vert', 'color.frag')
        self.text_shader    = BlueSkyProgram('text.vert', 'text.frag')
        self.text_shader.bind_uniform_buffer('global_data', self.globaldata)

        self.create_objects()
        self.update_lcd() 

def _drawToolMarkers(self):
        x, y, z = self.editor.level.playerSpawnPosition()
        
        GL.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA)
        GL.glEnable(GL.GL_BLEND)
        
        color = config.selectionColors.black.get() + (0.35,)
        GL.glColor(*color)
        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_LINE)
        GL.glLineWidth(2.0)
        drawCube(FloatBox((x, y, z), (1, 1, 1)))
        GL.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_FILL)
        drawCube(FloatBox((x, y, z), (1, 1, 1)))
        GL.glDisable(GL.GL_BLEND)
        
        GL.glEnable(GL.GL_DEPTH_TEST)
        GL.glColor(1.0, 1.0, 1.0, 1.0)
        self.drawCage(x, y, z)
        self.drawCharacterHead(x + 0.5, y + 0.5 + 0.125 * numpy.sin(self.editor.frames * 0.05), z + 0.5)
        GL.glDisable(GL.GL_DEPTH_TEST) 

def gl_draw_all(self, root, offset):
        if not self.visible:
            return
        from OpenGL import GL, GLU

        rect = self.rect.move(offset)
        if self.is_gl_container:
            self.gl_draw_self(root, offset)
            suboffset = rect.topleft
            for subwidget in self.subwidgets:
                subwidget.gl_draw_all(root, suboffset)
        else:
            try:
                surface = Surface(self.size, SRCALPHA)
            except Exception:
                #size error?
                return
            self.draw_all(surface)
            data = image.tostring(surface, 'RGBA', 1)
            w, h = root.size
            GL.glViewport(0, 0, w, h)
            GL.glMatrixMode(GL.GL_PROJECTION)
            GL.glLoadIdentity()
            GLU.gluOrtho2D(0, w, 0, h)
            GL.glMatrixMode(GL.GL_MODELVIEW)
            GL.glLoadIdentity()
            GL.glRasterPos2i(max(rect.left, 0), max(h - rect.bottom, 0))
            GL.glPushAttrib(GL.GL_COLOR_BUFFER_BIT)
            GL.glEnable(GL.GL_BLEND)
            GL.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA)
            GL.glDrawPixels(self.width, self.height,
                            GL.GL_RGBA, GL.GL_UNSIGNED_BYTE, fromstring(data, dtype='uint8'))
            GL.glPopAttrib()
            GL.glFlush() 

def drawCharacterHead(self, x, y, z, realCoords=None, dim=0):
        GL.glEnable(GL.GL_CULL_FACE)
        origin = (x - 0.25, y - 0.25, z - 0.25)
        size = (0.5, 0.5, 0.5)
        box = FloatBox(origin, size)
        
        hat_origin = (x - 0.275, y - 0.275, z - 0.275)
        hat_size = (0.55, 0.55, 0.55)
        hat_box = FloatBox(hat_origin, hat_size)

        if realCoords is not None and self.playerPos[dim][realCoords] != "Player" and config.settings.downloadPlayerSkins.get():
            drawCube(box,
                     texture=self.playerTexture[self.playerPos[dim][realCoords]], textureVertices=self.texVerts[0])
            GL.glEnable(GL.GL_BLEND)
            GL.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA)
            drawCube(hat_box,
                     texture=self.playerTexture[self.playerPos[dim][realCoords]], textureVertices=self.texVerts[1])
            GL.glDisable(GL.GL_BLEND)
        else:
            drawCube(box,
                     texture=self.charTex, textureVertices=self.texVerts[0])
        GL.glDisable(GL.GL_CULL_FACE)

    #@property
    #def statusText(self):
    #    if not self.panel:
    #        return ""
    #    player = self.panel.selectedPlayer
    #    if player == "Player":
    #        return "Click to move the player"
#
    #    return _("Click to move the player \"{0}\"").format(player) 

def initializeGL(self):
        GL.glClearColor(1.0, 0.0, 0.0, 1.0)
        GL.glEnable(GL.GL_BLEND)
        GL.glBlendFunc (GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA)
        GL.glClear(GL.GL_COLOR_BUFFER_BIT)

        print("OpenGL.GL: " + str(GL.glGetString(GL.GL_VERSION)))
        print("GL.GLSL: " + str(GL.glGetString(GL.GL_SHADING_LANGUAGE_VERSION)))
        print("OpenGL ATTRIBUTES:\n",", ".join(d for d in dir(GL) if d.startswith("GL_")))

        self.program = QOpenGLShaderProgram()
        self.program.addShaderFromSourceCode(QOpenGLShader.Vertex, """#version 120
        attribute vec2 position;
        attribute vec2 texcoord;
        varying vec2 mytexcoord;
        void main() {
            gl_Position = vec4(position, 0., 1.0);
            mytexcoord = texcoord;
        }""")

        self.program.addShaderFromSourceCode(QOpenGLShader.Fragment, """#version 120
        uniform sampler2D texture;
        varying vec2 mytexcoord;
        void main() {
            
            gl_FragColor = texture2D(texture,mytexcoord);
        }""")
        print(self.program.log())
        self.program.link()

        self.texture = fillTexture2d(np.outer(np.linspace(0, 1, 128), np.ones(128))) 

def initializeGL(self):
        """Initialize OpenGL, VBOs, upload data on the GPU, etc."""

        # First check for supported GL version
        gl_version = float(gl.glGetString(gl.GL_VERSION)[:3])
        if gl_version < 3.3:
            return

        # background color
        gl.glClearColor(0, 0, 0, 0)
        gl.glEnable(gl.GL_BLEND)
        gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)

        self.globaldata = ndUBO()

        try:
            # Compile shaders and link color shader program
            self.color_shader = BlueSkyProgram('data/graphics/shaders/nd-normal.vert', 'data/graphics/shaders/nd-color.frag')
            self.color_shader.bind_uniform_buffer('global_data', self.globaldata)

            # Compile shaders and link text shader program
            self.text_shader = BlueSkyProgram('data/graphics/shaders/nd-text.vert', 'data/graphics/shaders/nd-text.frag')
            self.text_shader.bind_uniform_buffer('global_data', self.globaldata)

        except RuntimeError as e:
            qCritical('Error compiling shaders in radarwidget: ' + e.args[0])
            return

        # Set initial zoom
        self.globaldata.set_zoom(4.0)

        self.create_objects() 

def gl_draw_all(self, root, offset):
        if not self.visible:
            return
        #from OpenGL import GL, GLU

        rect = self.rect.move(offset)
        if self.is_gl_container:
            self.gl_draw_self(root, offset)
            suboffset = rect.topleft
            for subwidget in self.subwidgets:
                subwidget.gl_draw_all(root, suboffset)
        else:
            try:
                surface = Surface(self.size, SRCALPHA)
            except:
                #size error?
                return
            self.draw_all(surface)
            data = image.tostring(surface, 'RGBA', 1)
            w, h = root.size
            GL.glViewport(0, 0, w, h)
            GL.glMatrixMode(GL.GL_PROJECTION)
            GL.glLoadIdentity()
            GLU.gluOrtho2D(0, w, 0, h)
            GL.glMatrixMode(GL.GL_MODELVIEW)
            GL.glLoadIdentity()
            GL.glRasterPos2i(max(rect.left, 0), max(h - rect.bottom, 0))
            GL.glPushAttrib(GL.GL_COLOR_BUFFER_BIT)
            GL.glEnable(GL.GL_BLEND)
            GL.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA)
            GL.glDrawPixels(self.width, self.height,
                            GL.GL_RGBA, GL.GL_UNSIGNED_BYTE, fromstring(data, dtype='uint8'))
            GL.glPopAttrib()
            GL.glFlush() 

def drawCharacterHead(self, x, y, z, realCoords=None, dim=0):
        GL.glEnable(GL.GL_CULL_FACE)
        origin = (x - 0.25, y - 0.25, z - 0.25)
        size = (0.5, 0.5, 0.5)
        box = FloatBox(origin, size)
        
        hat_origin = (x - 0.275, y - 0.275, z - 0.275)
        hat_size = (0.55, 0.55, 0.55)
        hat_box = FloatBox(hat_origin, hat_size)

        if realCoords is not None and self.playerPos[dim][realCoords] != "Player" and config.settings.downloadPlayerSkins.get():
            drawCube(box,
                     texture=self.playerTexture[self.playerPos[dim][realCoords]], textureVertices=self.texVerts[0])
            GL.glEnable(GL.GL_BLEND)
            GL.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA)
            drawCube(hat_box,
                     texture=self.playerTexture[self.playerPos[dim][realCoords]], textureVertices=self.texVerts[1])
            GL.glDisable(GL.GL_BLEND)
        else:
            drawCube(box,
                     texture=self.charTex, textureVertices=self.texVerts[0])
        GL.glDisable(GL.GL_CULL_FACE)

    #@property
    #def statusText(self):
    #    if not self.panel:
    #        return ""
    #    player = self.panel.selectedPlayer
    #    if player == "Player":
    #        return "Click to move the player"
#
    #    return _("Click to move the player \"{0}\"").format(player) 

def paintGL(self, p, opt, widget):
        p.beginNativePainting()
        import OpenGL.GL as gl
        
        ## set clipping viewport
        view = self.getViewBox()
        if view is not None:
            rect = view.mapRectToItem(self, view.boundingRect())
            #gl.glViewport(int(rect.x()), int(rect.y()), int(rect.width()), int(rect.height()))
            
            #gl.glTranslate(-rect.x(), -rect.y(), 0)
            
            gl.glEnable(gl.GL_STENCIL_TEST)
            gl.glColorMask(gl.GL_FALSE, gl.GL_FALSE, gl.GL_FALSE, gl.GL_FALSE) # disable drawing to frame buffer
            gl.glDepthMask(gl.GL_FALSE)  # disable drawing to depth buffer
            gl.glStencilFunc(gl.GL_NEVER, 1, 0xFF)  
            gl.glStencilOp(gl.GL_REPLACE, gl.GL_KEEP, gl.GL_KEEP)  
            
            ## draw stencil pattern
            gl.glStencilMask(0xFF)
            gl.glClear(gl.GL_STENCIL_BUFFER_BIT)
            gl.glBegin(gl.GL_TRIANGLES)
            gl.glVertex2f(rect.x(), rect.y())
            gl.glVertex2f(rect.x()+rect.width(), rect.y())
            gl.glVertex2f(rect.x(), rect.y()+rect.height())
            gl.glVertex2f(rect.x()+rect.width(), rect.y()+rect.height())
            gl.glVertex2f(rect.x()+rect.width(), rect.y())
            gl.glVertex2f(rect.x(), rect.y()+rect.height())
            gl.glEnd()
                       
            gl.glColorMask(gl.GL_TRUE, gl.GL_TRUE, gl.GL_TRUE, gl.GL_TRUE)
            gl.glDepthMask(gl.GL_TRUE)
            gl.glStencilMask(0x00)
            gl.glStencilFunc(gl.GL_EQUAL, 1, 0xFF)
            
        try:
            x, y = self.getData()
            pos = np.empty((len(x), 2))
            pos[:,0] = x
            pos[:,1] = y
            gl.glEnableClientState(gl.GL_VERTEX_ARRAY)
            try:
                gl.glVertexPointerf(pos)
                pen = fn.mkPen(self.opts['pen'])
                color = pen.color()
                gl.glColor4f(color.red()/255., color.green()/255., color.blue()/255., color.alpha()/255.)
                width = pen.width()
                if pen.isCosmetic() and width < 1:
                    width = 1
                gl.glPointSize(width)
                gl.glEnable(gl.GL_LINE_SMOOTH)
                gl.glEnable(gl.GL_BLEND)
                gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)
                gl.glHint(gl.GL_LINE_SMOOTH_HINT, gl.GL_NICEST)
                gl.glDrawArrays(gl.GL_LINE_STRIP, 0, pos.size / pos.shape[-1])
            finally:
                gl.glDisableClientState(gl.GL_VERTEX_ARRAY)
        finally:
            p.endNativePainting() 

def renderImage(self, context):
        width, height = self.getSize()
        gl.glViewport(0, 0, width, height)

        gl.glDisable(gl.GL_SCISSOR_TEST)

        gl.glEnable(gl.GL_ALPHA_TEST)
        gl.glAlphaFunc(gl.GL_GREATER, 0)

        gl.glEnable(gl.GL_BLEND)
        gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)

        self.frameBuffer.bind()

        self.renderer.render(context)

        self.frameBuffer.unbind()

        #TODO Restore blend state. Any other states that need restoring...?
        gl.glBlendFunc(gl.GL_ONE, gl.GL_ONE_MINUS_SRC_ALPHA) 

def initializeGL(self):
        """Initialize OpenGL, VBOs, upload data on the GPU, etc."""

        # First check for supported GL version
        gl_version = float(gl.glGetString(gl.GL_VERSION)[:3])
        if gl_version < 3.3:
            print(('OpenGL context created with GL version %.1f' % gl_version))
            qCritical("""Your system reports that it supports OpenGL up to version %.1f. The minimum requirement for BlueSky is OpenGL 3.3.
                Generally, AMD/ATI/nVidia cards from 2008 and newer support OpenGL 3.3, and Intel integrated graphics from the Haswell
                generation and newer. If you think your graphics system should be able to support GL>=3.3 please open an issue report
                on the BlueSky Github page (https://github.com/ProfHoekstra/bluesky/issues)""" % gl_version)
            return

        # background color
        gl.glClearColor(*(palette.background + (0,)))
        gl.glEnable(gl.GL_BLEND)
        gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)

        self.globaldata = radarUBO()

        try:
            shpath = path.join(settings.gfx_path, 'shaders')
            # Compile shaders and link color shader program
            self.color_shader = BlueSkyProgram(path.join(shpath, 'radarwidget-normal.vert'), path.join(shpath, 'radarwidget-color.frag'))
            self.color_shader.bind_uniform_buffer('global_data', self.globaldata)

            # Compile shaders and link texture shader program
            self.texture_shader = BlueSkyProgram(path.join(shpath, 'radarwidget-normal.vert'), path.join(shpath, 'radarwidget-texture.frag'))
            self.texture_shader.bind_uniform_buffer('global_data', self.globaldata)

            # Compile shaders and link text shader program
            self.text_shader = BlueSkyProgram(path.join(shpath, 'radarwidget-text.vert'), path.join(shpath, 'radarwidget-text.frag'))
            self.text_shader.bind_uniform_buffer('global_data', self.globaldata)

            self.ssd_shader = BlueSkyProgram(path.join(shpath, 'ssd.vert'), path.join(shpath, 'ssd.frag'), path.join(shpath, 'ssd.geom'))
            self.ssd_shader.bind_uniform_buffer('global_data', self.globaldata)
            self.ssd_shader.loc_vlimits = gl.glGetUniformLocation(self.ssd_shader.program, 'Vlimits')
            self.ssd_shader.loc_nac = gl.glGetUniformLocation(self.ssd_shader.program, 'n_ac')

        except RuntimeError as e:
            print('Error compiling shaders in radarwidget: ' + e.args[0])
            qCritical('Error compiling shaders in radarwidget: ' + e.args[0])
            return

        # create all vertex array objects
        try:
            self.create_objects()
        except Exception as e:
            print('Error while creating RadarWidget objects: ' + e.args[0]) 

def paintGL(self, p, opt, widget):
        p.beginNativePainting()
        import OpenGL.GL as gl
        
        ## set clipping viewport
        view = self.getViewBox()
        if view is not None:
            rect = view.mapRectToItem(self, view.boundingRect())
            #gl.glViewport(int(rect.x()), int(rect.y()), int(rect.width()), int(rect.height()))
            
            #gl.glTranslate(-rect.x(), -rect.y(), 0)
            
            gl.glEnable(gl.GL_STENCIL_TEST)
            gl.glColorMask(gl.GL_FALSE, gl.GL_FALSE, gl.GL_FALSE, gl.GL_FALSE) # disable drawing to frame buffer
            gl.glDepthMask(gl.GL_FALSE)  # disable drawing to depth buffer
            gl.glStencilFunc(gl.GL_NEVER, 1, 0xFF)  
            gl.glStencilOp(gl.GL_REPLACE, gl.GL_KEEP, gl.GL_KEEP)  
            
            ## draw stencil pattern
            gl.glStencilMask(0xFF)
            gl.glClear(gl.GL_STENCIL_BUFFER_BIT)
            gl.glBegin(gl.GL_TRIANGLES)
            gl.glVertex2f(rect.x(), rect.y())
            gl.glVertex2f(rect.x()+rect.width(), rect.y())
            gl.glVertex2f(rect.x(), rect.y()+rect.height())
            gl.glVertex2f(rect.x()+rect.width(), rect.y()+rect.height())
            gl.glVertex2f(rect.x()+rect.width(), rect.y())
            gl.glVertex2f(rect.x(), rect.y()+rect.height())
            gl.glEnd()
                       
            gl.glColorMask(gl.GL_TRUE, gl.GL_TRUE, gl.GL_TRUE, gl.GL_TRUE)
            gl.glDepthMask(gl.GL_TRUE)
            gl.glStencilMask(0x00)
            gl.glStencilFunc(gl.GL_EQUAL, 1, 0xFF)
            
        try:
            x, y = self.getData()
            pos = np.empty((len(x), 2))
            pos[:,0] = x
            pos[:,1] = y
            gl.glEnableClientState(gl.GL_VERTEX_ARRAY)
            try:
                gl.glVertexPointerf(pos)
                pen = fn.mkPen(self.opts['pen'])
                color = pen.color()
                gl.glColor4f(color.red()/255., color.green()/255., color.blue()/255., color.alpha()/255.)
                width = pen.width()
                if pen.isCosmetic() and width < 1:
                    width = 1
                gl.glPointSize(width)
                gl.glEnable(gl.GL_LINE_SMOOTH)
                gl.glEnable(gl.GL_BLEND)
                gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)
                gl.glHint(gl.GL_LINE_SMOOTH_HINT, gl.GL_NICEST)
                gl.glDrawArrays(gl.GL_LINE_STRIP, 0, pos.size / pos.shape[-1])
            finally:
                gl.glDisableClientState(gl.GL_VERTEX_ARRAY)
        finally:
            p.endNativePainting() 

def paintGL(self, p, opt, widget):
        p.beginNativePainting()
        import OpenGL.GL as gl
        
        ## set clipping viewport
        view = self.getViewBox()
        if view is not None:
            rect = view.mapRectToItem(self, view.boundingRect())
            #gl.glViewport(int(rect.x()), int(rect.y()), int(rect.width()), int(rect.height()))
            
            #gl.glTranslate(-rect.x(), -rect.y(), 0)
            
            gl.glEnable(gl.GL_STENCIL_TEST)
            gl.glColorMask(gl.GL_FALSE, gl.GL_FALSE, gl.GL_FALSE, gl.GL_FALSE) # disable drawing to frame buffer
            gl.glDepthMask(gl.GL_FALSE)  # disable drawing to depth buffer
            gl.glStencilFunc(gl.GL_NEVER, 1, 0xFF)  
            gl.glStencilOp(gl.GL_REPLACE, gl.GL_KEEP, gl.GL_KEEP)  
            
            ## draw stencil pattern
            gl.glStencilMask(0xFF)
            gl.glClear(gl.GL_STENCIL_BUFFER_BIT)
            gl.glBegin(gl.GL_TRIANGLES)
            gl.glVertex2f(rect.x(), rect.y())
            gl.glVertex2f(rect.x()+rect.width(), rect.y())
            gl.glVertex2f(rect.x(), rect.y()+rect.height())
            gl.glVertex2f(rect.x()+rect.width(), rect.y()+rect.height())
            gl.glVertex2f(rect.x()+rect.width(), rect.y())
            gl.glVertex2f(rect.x(), rect.y()+rect.height())
            gl.glEnd()
                       
            gl.glColorMask(gl.GL_TRUE, gl.GL_TRUE, gl.GL_TRUE, gl.GL_TRUE)
            gl.glDepthMask(gl.GL_TRUE)
            gl.glStencilMask(0x00)
            gl.glStencilFunc(gl.GL_EQUAL, 1, 0xFF)
            
        try:
            x, y = self.getData()
            pos = np.empty((len(x), 2))
            pos[:,0] = x
            pos[:,1] = y
            gl.glEnableClientState(gl.GL_VERTEX_ARRAY)
            try:
                gl.glVertexPointerf(pos)
                pen = fn.mkPen(self.opts['pen'])
                color = pen.color()
                gl.glColor4f(color.red()/255., color.green()/255., color.blue()/255., color.alpha()/255.)
                width = pen.width()
                if pen.isCosmetic() and width < 1:
                    width = 1
                gl.glPointSize(width)
                gl.glEnable(gl.GL_LINE_SMOOTH)
                gl.glEnable(gl.GL_BLEND)
                gl.glBlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA)
                gl.glHint(gl.GL_LINE_SMOOTH_HINT, gl.GL_NICEST)
                gl.glDrawArrays(gl.GL_LINE_STRIP, 0, pos.size / pos.shape[-1])
            finally:
                gl.glDisableClientState(gl.GL_VERTEX_ARRAY)
        finally:
            p.endNativePainting()