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    81b348c4
    GPencil Tools: Canvas rotate improvement · 81b348c4
    Pullusb authored
    In camera view : New rotate canvas pivot mode from view center instead of camera center (enabled by default).
    Fix rotate canvas precision in free navigation.
    Also now compatible with region overlap toggled off.
    81b348c4
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    GPencil Tools: Canvas rotate improvement
    Pullusb authored
    In camera view : New rotate canvas pivot mode from view center instead of camera center (enabled by default).
    Fix rotate canvas precision in free navigation.
    Also now compatible with region overlap toggled off.
rotate_canvas.py 11.71 KiB
from .prefs import get_addon_prefs

import bpy
import math
import mathutils
from bpy_extras.view3d_utils import location_3d_to_region_2d
from bpy.props import BoolProperty, EnumProperty
from time import time
## draw utils
import gpu
import bgl
import blf
from gpu_extras.batch import batch_for_shader
from gpu_extras.presets import draw_circle_2d

def step_value(value, step):
    '''return the step closer to the passed value'''
    abs_angle = abs(value)
    diff = abs_angle % step
    lower_step = abs_angle - diff
    higher_step = lower_step + step
    if abs_angle - lower_step < higher_step - abs_angle:
        return math.copysign(lower_step, value)
    else:
        return math.copysign(higher_step, value)

def draw_callback_px(self, context):
    # 50% alpha, 2 pixel width line
    if context.area != self.current_area:
        return
    shader = gpu.shader.from_builtin('2D_UNIFORM_COLOR')
    bgl.glEnable(bgl.GL_BLEND)
    bgl.glLineWidth(2)

    # init
    batch = batch_for_shader(shader, 'LINE_STRIP', {"pos": [self.center, self.initial_pos]})#self.vector_initial
    shader.bind()
    shader.uniform_float("color", (0.5, 0.5, 0.8, 0.6))
    batch.draw(shader)

    batch = batch_for_shader(shader, 'LINE_STRIP', {"pos": [self.center, self.pos_current]})
    shader.bind()
    shader.uniform_float("color", (0.3, 0.7, 0.2, 0.5))
    batch.draw(shader)

    ## debug lines
    # batch = batch_for_shader(shader, 'LINES', {"pos": [
    #     (0,0), (context.area.width, context.area.height),
    #     (context.area.width, 0), (0, context.area.height)
    #     ]})
    # shader.bind()
    # shader.uniform_float("color", (0.8, 0.1, 0.1, 0.5))
    # batch.draw(shader)

    # restore opengl defaults
    bgl.glLineWidth(1)
    bgl.glDisable(bgl.GL_BLEND)

    ## text
    font_id = 0
    ## draw text debug infos
    blf.position(font_id, 15, 30, 0)
    blf.size(font_id, 20, 72)
    blf.draw(font_id, f'angle: {math.degrees(self.angle):.1f}')


class RC_OT_RotateCanvas(bpy.types.Operator):
    bl_idname = 'view3d.rotate_canvas'
    bl_label = 'Rotate Canvas'
    bl_options = {"REGISTER", "UNDO"}

    def get_center_view(self, context, cam):
        '''
        https://blender.stackexchange.com/questions/6377/coordinates-of-corners-of-camera-view-border
        Thanks to ideasman42
        '''

        frame = cam.data.view_frame()
        mat = cam.matrix_world
        frame = [mat @ v for v in frame]
        frame_px = [location_3d_to_region_2d(context.region, context.space_data.region_3d, v) for v in frame]
        center_x = frame_px[2].x + (frame_px[0].x - frame_px[2].x)/2
        center_y = frame_px[1].y + (frame_px[0].y - frame_px[1].y)/2

        return mathutils.Vector((center_x, center_y))

    def execute(self, context):
        if self.hud:
            bpy.types.SpaceView3D.draw_handler_remove(self._handle, 'WINDOW')
            context.area.tag_redraw()
        if self.in_cam:
                self.cam.rotation_mode = self.org_rotation_mode
        return {'FINISHED'}


    def modal(self, context, event):
        if event.type in {'MOUSEMOVE'}:#,'INBETWEEN_MOUSEMOVE'
            # Get current mouse coordination (region)
            self.pos_current = mathutils.Vector((event.mouse_region_x, event.mouse_region_y))
            # Get current vector
            self.vector_current = (self.pos_current - self.center).normalized()
            # Calculates the angle between initial and current vectors
            self.angle = self.vector_initial.angle_signed(self.vector_current)#radian
            # print (math.degrees(self.angle), self.vector_initial, self.vector_current)


            ## handle snap key
            snap = False
            if self.snap_ctrl and event.ctrl:
                snap = True
            if self.snap_shift and event.shift:
                snap = True
            if self.snap_alt and event.alt:
                snap = True
            ## Snapping to specific degrees angle
            if snap:
                self.angle = step_value(self.angle, self.snap_step)

            if self.in_cam:
                self.cam.matrix_world = self.cam_matrix
                self.cam.rotation_euler.rotate_axis("Z", self.angle)

                if self.use_view_center:
                    ## apply inverse of the rotation on view offset in cam rotate from view center
                    neg = -self.angle
                    rot_mat2d = mathutils.Matrix([[math.cos(neg), -math.sin(neg)], [math.sin(neg), math.cos(neg)]])

                    # scale_mat = mathutils.Matrix([[1.0, 0.0], [0.0, self.ratio]])
                    new_cam_offset = self.view_cam_offset.copy()

                    ## area deformation correction
                    new_cam_offset = mathutils.Vector((new_cam_offset[0], new_cam_offset[1] * self.ratio))

                    ## rotate by matrix
                    new_cam_offset.rotate(rot_mat2d)

                    ## area deformation restore
                    new_cam_offset = mathutils.Vector((new_cam_offset[0], new_cam_offset[1] * self.ratio_inv))
                    
                    context.space_data.region_3d.view_camera_offset = new_cam_offset

            else: # free view
                context.space_data.region_3d.view_rotation = self._rotation
                rot = context.space_data.region_3d.view_rotation
                rot = rot.to_euler()
                rot.rotate_axis("Z", self.angle)
                context.space_data.region_3d.view_rotation = rot.to_quaternion()

        if event.type in {'RIGHTMOUSE', 'LEFTMOUSE', 'MIDDLEMOUSE'} and event.value == 'RELEASE':
            # Trigger reset : Less than 150ms and less than 2 degrees move
            if time() - self.timer < 0.15 and abs(math.degrees(self.angle)) < 2:
                # self.report({'INFO'}, 'Reset')
                aim = context.space_data.region_3d.view_rotation @ mathutils.Vector((0.0, 0.0, 1.0))#view vector
                z_up_quat = aim.to_track_quat('Z','Y')#track Z, up Y
                if self.in_cam:
                    if self.cam.parent:
                        cam_quat = self.cam.parent.matrix_world.inverted().to_quaternion() @ z_up_quat
                    else:
                        cam_quat = z_up_quat
                    self.cam.rotation_euler = cam_quat.to_euler('XYZ')
                else:
                    context.space_data.region_3d.view_rotation = z_up_quat
            self.execute(context)
            return {'FINISHED'}

        if event.type == 'ESC':#Cancel
            self.execute(context)
            if self.in_cam:
                self.cam.matrix_world = self.cam_matrix
                context.space_data.region_3d.view_camera_offset = self.view_cam_offset
            else:
                context.space_data.region_3d.view_rotation = self._rotation
            return {'CANCELLED'}

        return {'RUNNING_MODAL'}

    def invoke(self, context, event):
        self.current_area = context.area
        prefs = get_addon_prefs()
        self.hud = prefs.canvas_use_hud
        self.use_view_center = prefs.canvas_use_view_center
        self.angle = 0.0
        self.in_cam = context.region_data.view_perspective == 'CAMERA'

        ## store ratio for view rotate correction

        # CORRECT UI OVERLAP FROM HEADER TOOLBAR
        regs = context.area.regions
        if context.preferences.system.use_region_overlap:
            w = context.area.width 
            # minus tool header
            h = context.area.height - regs[0].height
        else:
            # minus tool leftbar + sidebar right
            w = context.area.width - regs[2].width - regs[3].width
            # minus tool header + header
            h = context.area.height - regs[0].height - regs[1].height
        
        self.ratio = h / w
        self.ratio_inv = w / h    

        if self.in_cam:
            # Get camera from scene
            self.cam = bpy.context.scene.camera

            #return if one element is locked (else bypass location)
            if self.cam.lock_rotation[:] != (False, False, False):
                self.report({'WARNING'}, 'Camera rotation is locked')
                return {'CANCELLED'}
            
            if self.use_view_center:                
                self.center = mathutils.Vector((w/2, h/2))
            else:
                self.center = self.get_center_view(context, self.cam)

            # store original rotation mode
            self.org_rotation_mode = self.cam.rotation_mode
            # set to euler to works with quaternions, restored at finish
            self.cam.rotation_mode = 'XYZ'
            # store camera matrix world
            self.cam_matrix = self.cam.matrix_world.copy()
            # self.cam_init_euler = self.cam.rotation_euler.copy()
            
            ## initialize current view_offset in camera
            self.view_cam_offset = mathutils.Vector(context.space_data.region_3d.view_camera_offset)

        else:
            self.center = mathutils.Vector((w/2, h/2))
            # self.center = mathutils.Vector((context.area.width/2, context.area.height/2))

            # store current rotation
            self._rotation = context.space_data.region_3d.view_rotation.copy()

        # Get current mouse coordination
        self.pos_current = mathutils.Vector((event.mouse_region_x, event.mouse_region_y))

        self.initial_pos = self.pos_current# for draw debug, else no need
        # Calculate inital vector
        self.vector_initial = self.pos_current - self.center
        self.vector_initial.normalize()

        # Initializes the current vector with the same initial vector.
        self.vector_current = self.vector_initial.copy()


        #Snap keys
        self.snap_ctrl = not prefs.use_ctrl
        self.snap_shift = not prefs.use_shift
        self.snap_alt = not prefs.use_alt
        # round to closer degree and convert back to radians
        self.snap_step = math.radians(round(math.degrees(prefs.rc_angle_step)))

        self.timer = time()
        args = (self, context)
        if self.hud:
            self._handle = bpy.types.SpaceView3D.draw_handler_add(draw_callback_px, args, 'WINDOW', 'POST_PIXEL')
        context.window_manager.modal_handler_add(self)
        return {'RUNNING_MODAL'}


## -- Set / Reset rotation buttons

class RC_OT_Set_rotation(bpy.types.Operator):
    bl_idname = 'view3d.rotate_canvas_set'
    bl_label = 'Save Rotation'
    bl_description = 'Save active camera rotation (per camera property)'
    bl_options = {"REGISTER"}

    @classmethod
    def poll(cls, context):
        return context.space_data.region_3d.view_perspective == 'CAMERA'

    def execute(self, context):
        cam_ob = context.scene.camera
        cam_ob['stored_rotation'] = cam_ob.rotation_euler
        if not cam_ob.get('_RNA_UI'):
            cam_ob['_RNA_UI'] = {}
            cam_ob['_RNA_UI']["stored_rotation"] = {
                    "description":"Stored camera rotation (Gpencil tools > rotate canvas operator)",
                    "subtype":'EULER',
                    # "is_overridable_library":0,
                    }

        return {'FINISHED'}

class RC_OT_Reset_rotation(bpy.types.Operator):
    bl_idname = 'view3d.rotate_canvas_reset'
    bl_label = 'Restore Rotation'
    bl_description = 'Restore active camera rotation from previously saved state'
    bl_options = {"REGISTER", "UNDO"}

    @classmethod
    def poll(cls, context):
        return context.space_data.region_3d.view_perspective == 'CAMERA' and context.scene.camera.get('stored_rotation')

    def execute(self, context):
        cam_ob = context.scene.camera
        cam_ob.rotation_euler = cam_ob['stored_rotation']
        return {'FINISHED'}


### --- REGISTER

classes = (
    RC_OT_RotateCanvas,
    RC_OT_Set_rotation,
    RC_OT_Reset_rotation,
)

def register():
    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():
    for cls in reversed(classes):
        bpy.utils.unregister_class(cls)