/** Save the current OpenGL state and initialize OpenGL for 2D
 * rendering. glaEnd2DDraw should be called on the returned structure
 * to free it and to return OpenGL to its previous state. The
 * scissor rectangle is set to match the viewport.
 *
 * See glaDefine2DArea for an explanation of why this function uses integers.
 *
 * \param screen_rect The screen rectangle to be used for 2D drawing.
 * \param world_rect The world rectangle that the 2D area represented
 * by \a screen_rect is supposed to represent. If NULL it is assumed the
 * world has a 1 to 1 mapping to the screen.
 */
gla2DDrawInfo *glaBegin2DDraw(rcti *screen_rect, rctf *world_rect) 
{
	gla2DDrawInfo *di = MEM_mallocN(sizeof(*di), "gla2DDrawInfo");
	int sc_w, sc_h;
	float wo_w, wo_h;

	glGetIntegerv(GL_VIEWPORT, (GLint *)di->orig_vp);
	glGetIntegerv(GL_SCISSOR_BOX, (GLint *)di->orig_sc);
	glGetFloatv(GL_PROJECTION_MATRIX, (GLfloat *)di->orig_projmat);
	glGetFloatv(GL_MODELVIEW_MATRIX, (GLfloat *)di->orig_viewmat);

	di->screen_rect = *screen_rect;
	if (world_rect) {
		di->world_rect = *world_rect;
	}
	else {
		di->world_rect.xmin = di->screen_rect.xmin;
		di->world_rect.ymin = di->screen_rect.ymin;
		di->world_rect.xmax = di->screen_rect.xmax;
		di->world_rect.ymax = di->screen_rect.ymax;
	}

	sc_w = BLI_rcti_size_x(&di->screen_rect);
	sc_h = BLI_rcti_size_y(&di->screen_rect);
	wo_w = BLI_rcti_size_x(&di->world_rect);
	wo_h = BLI_rcti_size_y(&di->world_rect);

	di->wo_to_sc[0] = sc_w / wo_w;
	di->wo_to_sc[1] = sc_h / wo_h;

	glaDefine2DArea(&di->screen_rect);

	return di;
}

void UI_fontstyle_draw_ex(
        const uiFontStyle *fs, const rcti *rect, const char *str,
        size_t len, float *r_xofs, float *r_yofs)
{
	int xofs = 0, yofs;
	int font_flag = BLF_CLIPPING;

	UI_fontstyle_set(fs);

	/* set the flag */
	if (fs->shadow) {
		font_flag |= BLF_SHADOW;
		const float shadow_color[4] = {fs->shadowcolor, fs->shadowcolor, fs->shadowcolor, fs->shadowalpha};
		BLF_shadow(fs->uifont_id, fs->shadow, shadow_color);
		BLF_shadow_offset(fs->uifont_id, fs->shadx, fs->shady);
	}
	if (fs->kerning == 1) {
		font_flag |= BLF_KERNING_DEFAULT;
	}
	if (fs->word_wrap == 1) {
		font_flag |= BLF_WORD_WRAP;
	}

	BLF_enable(fs->uifont_id, font_flag);

	if (fs->word_wrap == 1) {
		/* draw from boundbox top */
		yofs = BLI_rcti_size_y(rect) - BLF_height_max(fs->uifont_id);
	}
	else {
		/* draw from boundbox center */
		yofs = ceil(0.5f * (BLI_rcti_size_y(rect) - BLF_ascender(fs->uifont_id)));
	}

	if (fs->align == UI_STYLE_TEXT_CENTER) {
		xofs = floor(0.5f * (BLI_rcti_size_x(rect) - BLF_width(fs->uifont_id, str, len)));
		/* don't center text if it chops off the start of the text, 2 gives some margin */
		if (xofs < 2) {
			xofs = 2;
		}
	}
	else if (fs->align == UI_STYLE_TEXT_RIGHT) {
		xofs = BLI_rcti_size_x(rect) - BLF_width(fs->uifont_id, str, len) - 0.1f * U.widget_unit;
	}

	/* clip is very strict, so we give it some space */
	BLF_clipping(fs->uifont_id, rect->xmin - 2, rect->ymin - 4, rect->xmax + 1, rect->ymax + 4);
	BLF_position(fs->uifont_id, rect->xmin + xofs, rect->ymin + yofs, 0.0f);

	BLF_draw(fs->uifont_id, str, len);

	BLF_disable(fs->uifont_id, font_flag);

	*r_xofs = xofs;
	*r_yofs = yofs;
}

void gla2DSetMap(gla2DDrawInfo *di, rctf *rect) 
{
	int sc_w, sc_h;
	float wo_w, wo_h;

	di->world_rect = *rect;
	
	sc_w = BLI_rcti_size_x(&di->screen_rect);
	sc_h = BLI_rcti_size_y(&di->screen_rect);
	wo_w = BLI_rcti_size_x(&di->world_rect);
	wo_h = BLI_rcti_size_y(&di->world_rect);
	
	di->wo_to_sc[0] = sc_w / wo_w;
	di->wo_to_sc[1] = sc_h / wo_h;
}

/* tweak and line gestures */
int wm_gesture_evaluate(wmGesture *gesture)
{
	if (gesture->type == WM_GESTURE_TWEAK) {
		rcti *rect = gesture->customdata;
		int dx = BLI_rcti_size_x(rect);
		int dy = BLI_rcti_size_y(rect);
		if (ABS(dx) + ABS(dy) > U.tweak_threshold) {
			int theta = (int)floor(4.0f * atan2f((float)dy, (float)dx) / (float)M_PI + 0.5f);
			int val = EVT_GESTURE_W;

			if (theta == 0) val = EVT_GESTURE_E;
			else if (theta == 1) val = EVT_GESTURE_NE;
			else if (theta == 2) val = EVT_GESTURE_N;
			else if (theta == 3) val = EVT_GESTURE_NW;
			else if (theta == -1) val = EVT_GESTURE_SE;
			else if (theta == -2) val = EVT_GESTURE_S;
			else if (theta == -3) val = EVT_GESTURE_SW;
			
#if 0
			/* debug */
			if (val == 1) printf("tweak north\n");
			if (val == 2) printf("tweak north-east\n");
			if (val == 3) printf("tweak east\n");
			if (val == 4) printf("tweak south-east\n");
			if (val == 5) printf("tweak south\n");
			if (val == 6) printf("tweak south-west\n");
			if (val == 7) printf("tweak west\n");
			if (val == 8) printf("tweak north-west\n");
#endif
			return val;
		}
	}
	return 0;
}

static int node_circleselect_exec(bContext *C, wmOperator *op)
{
	SpaceNode *snode = CTX_wm_space_node(C);
	ARegion *ar = CTX_wm_region(C);
	bNode *node;

	int x, y, radius, gesture_mode;
	float offset[2];

	float zoom  = (float)(BLI_rcti_size_x(&ar->winrct)) / (float)(BLI_rctf_size_x(&ar->v2d.cur));

	gesture_mode = RNA_int_get(op->ptr, "gesture_mode");

	/* get operator properties */
	x = RNA_int_get(op->ptr, "x");
	y = RNA_int_get(op->ptr, "y");
	radius = RNA_int_get(op->ptr, "radius");

	UI_view2d_region_to_view(&ar->v2d, x, y, &offset[0], &offset[1]);

	for (node = snode->edittree->nodes.first; node; node = node->next) {
		if (BLI_rctf_isect_circle(&node->totr, offset, radius / zoom)) {
			nodeSetSelected(node, (gesture_mode == GESTURE_MODAL_SELECT));
		}
	}

	WM_event_add_notifier(C, NC_NODE | NA_SELECTED, NULL);

	return OPERATOR_FINISHED;
}

/* draw the contents of the sequencer strips view */
static void draw_seq_strips(const bContext *C, Editing *ed, ARegion *ar)
{
	Scene *scene = CTX_data_scene(C);
	View2D *v2d = &ar->v2d;
	Sequence *last_seq = BKE_sequencer_active_get(scene);
	int sel = 0, j;
	float pixelx = BLI_rctf_size_x(&v2d->cur) / BLI_rcti_size_x(&v2d->mask);
	
	/* loop through twice, first unselected, then selected */
	for (j = 0; j < 2; j++) {
		Sequence *seq;
		int outline_tint = (j) ? -60 : -150; /* highlighting around strip edges indicating selection */
		
		/* loop through strips, checking for those that are visible */
		for (seq = ed->seqbasep->first; seq; seq = seq->next) {
			/* boundbox and selection tests for NOT drawing the strip... */
			if ((seq->flag & SELECT) != sel) continue;
			else if (seq == last_seq) continue;
			else if (min_ii(seq->startdisp, seq->start) > v2d->cur.xmax) continue;
			else if (max_ii(seq->enddisp, seq->start + seq->len) < v2d->cur.xmin) continue;
			else if (seq->machine + 1.0f < v2d->cur.ymin) continue;
			else if (seq->machine > v2d->cur.ymax) continue;
			
			/* strip passed all tests unscathed... so draw it now */
			draw_seq_strip(scene, ar, seq, outline_tint, pixelx);
		}
		
		/* draw selected next time round */
		sel = SELECT;
	}
	
	/* draw the last selected last (i.e. 'active' in other parts of Blender), removes some overlapping error */
	if (last_seq)
		draw_seq_strip(scene, ar, last_seq, 120, pixelx);
}

void UI_fontstyle_draw_ex(
        const uiFontStyle *fs, const rcti *rect, const char *str,
        size_t len, float *r_xofs, float *r_yofs)
{
	float height;
	int xofs = 0, yofs;
	
	UI_fontstyle_set(fs);

	height = BLF_ascender(fs->uifont_id);
	yofs = ceil(0.5f * (BLI_rcti_size_y(rect) - height));

	if (fs->align == UI_STYLE_TEXT_CENTER) {
		xofs = floor(0.5f * (BLI_rcti_size_x(rect) - BLF_width(fs->uifont_id, str, len)));
		/* don't center text if it chops off the start of the text, 2 gives some margin */
		if (xofs < 2) {
			xofs = 2;
		}
	}
	else if (fs->align == UI_STYLE_TEXT_RIGHT) {
		xofs = BLI_rcti_size_x(rect) - BLF_width(fs->uifont_id, str, len) - 0.1f * U.widget_unit;
	}
	
	/* clip is very strict, so we give it some space */
	BLF_clipping(fs->uifont_id, rect->xmin - 2, rect->ymin - 4, rect->xmax + 1, rect->ymax + 4);
	BLF_enable(fs->uifont_id, BLF_CLIPPING);
	BLF_position(fs->uifont_id, rect->xmin + xofs, rect->ymin + yofs, 0.0f);

	if (fs->shadow) {
		BLF_enable(fs->uifont_id, BLF_SHADOW);
		BLF_shadow(fs->uifont_id, fs->shadow, fs->shadowcolor, fs->shadowcolor, fs->shadowcolor, fs->shadowalpha);
		BLF_shadow_offset(fs->uifont_id, fs->shadx, fs->shady);
	}

	if (fs->kerning == 1)
		BLF_enable(fs->uifont_id, BLF_KERNING_DEFAULT);

	BLF_draw(fs->uifont_id, str, len);
	BLF_disable(fs->uifont_id, BLF_CLIPPING);
	if (fs->shadow)
		BLF_disable(fs->uifont_id, BLF_SHADOW);
	if (fs->kerning == 1)
		BLF_disable(fs->uifont_id, BLF_KERNING_DEFAULT);

	*r_xofs = xofs;
	*r_yofs = yofs;
}

/* tweak and line gestures */
int wm_gesture_evaluate(wmGesture *gesture, const wmEvent *event)
{
  if (gesture->type == WM_GESTURE_TWEAK) {
    rcti *rect = gesture->customdata;
    const int delta[2] = {
        BLI_rcti_size_x(rect),
        BLI_rcti_size_y(rect),
    };

    if (WM_event_drag_test_with_delta(event, delta)) {
      int theta = round_fl_to_int(4.0f * atan2f((float)delta[1], (float)delta[0]) / (float)M_PI);
      int val = EVT_GESTURE_W;

      if (theta == 0) {
        val = EVT_GESTURE_E;
      }
      else if (theta == 1) {
        val = EVT_GESTURE_NE;
      }
      else if (theta == 2) {
        val = EVT_GESTURE_N;
      }
      else if (theta == 3) {
        val = EVT_GESTURE_NW;
      }
      else if (theta == -1) {
        val = EVT_GESTURE_SE;
      }
      else if (theta == -2) {
        val = EVT_GESTURE_S;
      }
      else if (theta == -3) {
        val = EVT_GESTURE_SW;
      }

#if 0
      /* debug */
      if (val == 1)
        printf("tweak north\n");
      if (val == 2)
        printf("tweak north-east\n");
      if (val == 3)
        printf("tweak east\n");
      if (val == 4)
        printf("tweak south-east\n");
      if (val == 5)
        printf("tweak south\n");
      if (val == 6)
        printf("tweak south-west\n");
      if (val == 7)
        printf("tweak west\n");
      if (val == 8)
        printf("tweak north-west\n");
#endif
      return val;
    }
  }
  return 0;
}

/* uses UI_BTYPE_ROUNDBOX button in block to get the rect */
static bool ed_preview_draw_rect(ScrArea *sa, int split, int first, rcti *rect, rcti *newrect)
{
	Render *re;
	RenderResult rres;
	char name[32];
	int offx = 0;
	int newx = BLI_rcti_size_x(rect);
	int newy = BLI_rcti_size_y(rect);
	bool ok = false;

	if (!split || first) sprintf(name, "Preview %p", (void *)sa);
	else sprintf(name, "SecondPreview %p", (void *)sa);

	if (split) {
		if (first) {
			offx = 0;
			newx = newx / 2;
		}
		else {
			offx = newx / 2;
			newx = newx - newx / 2;
		}
	}

	/* test if something rendered ok */
	re = RE_GetRender(name);

	/* material preview only needs monoscopy (view 0) */
	RE_AcquireResultImage(re, &rres, 0);

	if (rres.rectf) {
		
		if (ABS(rres.rectx - newx) < 2 && ABS(rres.recty - newy) < 2) {

			newrect->xmax = max_ii(newrect->xmax, rect->xmin + rres.rectx + offx);
			newrect->ymax = max_ii(newrect->ymax, rect->ymin + rres.recty);

			if (rres.rectx && rres.recty) {
				unsigned char *rect_byte = MEM_mallocN(rres.rectx * rres.recty * sizeof(int), "ed_preview_draw_rect");
				float fx = rect->xmin + offx;
				float fy = rect->ymin;

				/* material preview only needs monoscopy (view 0) */
				if (re)
					RE_AcquiredResultGet32(re, &rres, (unsigned int *)rect_byte, 0);

				glaDrawPixelsSafe(fx, fy, rres.rectx, rres.recty, rres.rectx, GL_RGBA, GL_UNSIGNED_BYTE, rect_byte);
				
				MEM_freeN(rect_byte);
				
				ok = 1;
			}
		}
	}

	RE_ReleaseResultImage(re);

	return ok;
}

/* called from drawview.c, as an extra per-window draw option */
void drawPropCircle(const struct bContext *C, TransInfo *t)
{
  if (t->flag & T_PROP_EDIT) {
    RegionView3D *rv3d = CTX_wm_region_view3d(C);
    float tmat[4][4], imat[4][4];
    int depth_test_enabled;

    if (t->spacetype == SPACE_VIEW3D && rv3d != NULL) {
      copy_m4_m4(tmat, rv3d->viewmat);
      invert_m4_m4(imat, tmat);
    }
    else {
      unit_m4(tmat);
      unit_m4(imat);
    }

    GPU_matrix_push();

    if (t->spacetype == SPACE_VIEW3D) {
      /* pass */
    }
    else if (t->spacetype == SPACE_IMAGE) {
      GPU_matrix_scale_2f(1.0f / t->aspect[0], 1.0f / t->aspect[1]);
    }
    else if (ELEM(t->spacetype, SPACE_GRAPH, SPACE_ACTION)) {
      /* only scale y */
      rcti *mask = &t->ar->v2d.mask;
      rctf *datamask = &t->ar->v2d.cur;
      float xsize = BLI_rctf_size_x(datamask);
      float ysize = BLI_rctf_size_y(datamask);
      float xmask = BLI_rcti_size_x(mask);
      float ymask = BLI_rcti_size_y(mask);
      GPU_matrix_scale_2f(1.0f, (ysize / xsize) * (xmask / ymask));
    }

    depth_test_enabled = GPU_depth_test_enabled();
    if (depth_test_enabled) {
      GPU_depth_test(false);
    }

    uint pos = GPU_vertformat_attr_add(immVertexFormat(), "pos", GPU_COMP_F32, 3, GPU_FETCH_FLOAT);

    immBindBuiltinProgram(GPU_SHADER_3D_UNIFORM_COLOR);
    immUniformThemeColor(TH_GRID);

    set_inverted_drawing(1);
    imm_drawcircball(t->center_global, t->prop_size, imat, pos);
    set_inverted_drawing(0);

    immUnbindProgram();

    if (depth_test_enabled) {
      GPU_depth_test(true);
    }

    GPU_matrix_pop();
  }
}

/* nothing drawn here, we use it to store values */
static void preview_cb(ScrArea *sa, struct uiBlock *block)
{
    SpaceImage *sima = sa->spacedata.first;
    rctf dispf;
    rcti *disprect = &G.scene->r.disprect;
    int winx = (G.scene->r.size * G.scene->r.xsch) / 100;
    int winy = (G.scene->r.size * G.scene->r.ysch) / 100;
    int mval[2];

    if (G.scene->r.mode & R_BORDER) {
        winx *= BLI_rcti_size_x(&G.scene->r.border);
        winy *= BLI_rctf_size_y(&G.scene->r.border);
    }

    /* while dragging we need to update the rects, otherwise it doesn't end with correct one */

    BLI_rctf_init(&dispf, 15.0f, BLI_rcti_size_x(&block->rect) - 15.0f, 15.0f, (BLI_rctf_size_y(&block->rect)) - 15.0f);
    ui_graphics_to_window_rct(sa->win, &dispf, disprect);

    /* correction for gla draw */
    BLI_rcti_translate(disprect, -curarea->winrct.xmin, -curarea->winrct.ymin);

    calc_image_view(sima, 'p');
//	printf("winrct %d %d %d %d\n", disprect->xmin, disprect->ymin, disprect->xmax, disprect->ymax);
    /* map to image space coordinates */
    mval[0] = disprect->xmin;
    mval[1] = disprect->ymin;
    areamouseco_to_ipoco(v2d, mval, &dispf.xmin, &dispf.ymin);
    mval[0] = disprect->xmax;
    mval[1] = disprect->ymax;
    areamouseco_to_ipoco(v2d, mval, &dispf.xmax, &dispf.ymax);

    /* map to render coordinates */
    disprect->xmin = dispf.xmin;
    disprect->xmax = dispf.xmax;
    disprect->ymin = dispf.ymin;
    disprect->ymax = dispf.ymax;

    CLAMP(disprect->xmin, 0, winx);
    CLAMP(disprect->xmax, 0, winx);
    CLAMP(disprect->ymin, 0, winy);
    CLAMP(disprect->ymax, 0, winy);
//	printf("drawrct %d %d %d %d\n", disprect->xmin, disprect->ymin, disprect->xmax, disprect->ymax);

}

void ED_space_image_get_zoom(SpaceImage *sima, ARegion *ar, float *zoomx, float *zoomy)
{
	int width, height;

	ED_space_image_get_size(sima, &width, &height);

	*zoomx = (float)(BLI_rcti_size_x(&ar->winrct) + 1) / (float)(BLI_rctf_size_x(&ar->v2d.cur) * width);
	*zoomy = (float)(BLI_rcti_size_y(&ar->winrct) + 1) / (float)(BLI_rctf_size_y(&ar->v2d.cur) * height);
}

void BLI_rcti_scale(rcti *rect, const float scale)
{
	const int cent_x      = BLI_rcti_cent_x(rect);
	const int cent_y      = BLI_rcti_cent_y(rect);
	const int size_x_half = BLI_rcti_size_x(rect) * (scale * 0.5f);
	const int size_y_half = BLI_rcti_size_y(rect) * (scale * 0.5f);
	rect->xmin = cent_x - size_x_half;
	rect->ymin = cent_y - size_y_half;
	rect->xmax = cent_x + size_x_half;
	rect->ymax = cent_y + size_y_half;
}

void wmViewport(const rcti *winrct)
{
  int width = BLI_rcti_size_x(winrct) + 1;
  int height = BLI_rcti_size_y(winrct) + 1;

  glViewport(winrct->xmin, winrct->ymin, width, height);
  glScissor(winrct->xmin, winrct->ymin, width, height);

  wmOrtho2_pixelspace(width, height);
  GPU_matrix_identity_set();
}

/* drawn same as above, but at 90 degree angle */
void UI_fontstyle_draw_rotated(const uiFontStyle *fs, const rcti *rect, const char *str)
{
	float height;
	int xofs, yofs;
	float angle;
	rcti txtrect;

	UI_fontstyle_set(fs);

	height = BLF_ascender(fs->uifont_id);
	/* becomes x-offset when rotated */
	xofs = ceil(0.5f * (BLI_rcti_size_y(rect) - height));

	/* ignore UI_STYLE, always aligned to top */

	/* rotate counter-clockwise for now (assumes left-to-right language)*/
	xofs += height;
	yofs = BLF_width(fs->uifont_id, str, BLF_DRAW_STR_DUMMY_MAX) + 5;
	angle = M_PI_2;

	/* translate rect to vertical */
	txtrect.xmin = rect->xmin - BLI_rcti_size_y(rect);
	txtrect.ymin = rect->ymin - BLI_rcti_size_x(rect);
	txtrect.xmax = rect->xmin;
	txtrect.ymax = rect->ymin;

	/* clip is very strict, so we give it some space */
	/* clipping is done without rotation, so make rect big enough to contain both positions */
	BLF_clipping(fs->uifont_id, txtrect.xmin - 1, txtrect.ymin - yofs - xofs - 4, rect->xmax + 1, rect->ymax + 4);
	BLF_enable(fs->uifont_id, BLF_CLIPPING);
	BLF_position(fs->uifont_id, txtrect.xmin + xofs, txtrect.ymax - yofs, 0.0f);

	BLF_enable(fs->uifont_id, BLF_ROTATION);
	BLF_rotation(fs->uifont_id, angle);

	if (fs->shadow) {
		BLF_enable(fs->uifont_id, BLF_SHADOW);
		const float shadow_color[4] = {fs->shadowcolor, fs->shadowcolor, fs->shadowcolor, fs->shadowalpha};
		BLF_shadow(fs->uifont_id, fs->shadow, shadow_color);
		BLF_shadow_offset(fs->uifont_id, fs->shadx, fs->shady);
	}

	if (fs->kerning == 1)
		BLF_enable(fs->uifont_id, BLF_KERNING_DEFAULT);

	BLF_draw(fs->uifont_id, str, BLF_DRAW_STR_DUMMY_MAX);
	BLF_disable(fs->uifont_id, BLF_ROTATION);
	BLF_disable(fs->uifont_id, BLF_CLIPPING);
	if (fs->shadow)
		BLF_disable(fs->uifont_id, BLF_SHADOW);
	if (fs->kerning == 1)
		BLF_disable(fs->uifont_id, BLF_KERNING_DEFAULT);
}

void wmGetProjectionMatrix(float mat[4][4], const rcti *winrct)
{
  int width = BLI_rcti_size_x(winrct) + 1;
  int height = BLI_rcti_size_y(winrct) + 1;
  orthographic_m4(mat,
                  -GLA_PIXEL_OFS,
                  (float)width - GLA_PIXEL_OFS,
                  -GLA_PIXEL_OFS,
                  (float)height - GLA_PIXEL_OFS,
                  -100,
                  100);
}

/* called from drawview.c, as an extra per-window draw option */
void drawPropCircle(const struct bContext *C, TransInfo *t)
{
	if (t->flag & T_PROP_EDIT) {
		RegionView3D *rv3d = CTX_wm_region_view3d(C);
		float tmat[4][4], imat[4][4];
		int depth_test_enabled;

		UI_ThemeColor(TH_GRID);

		if (t->spacetype == SPACE_VIEW3D && rv3d != NULL) {
			copy_m4_m4(tmat, rv3d->viewmat);
			invert_m4_m4(imat, tmat);
		}
		else {
			unit_m4(tmat);
			unit_m4(imat);
		}

		glPushMatrix();

		if (t->spacetype == SPACE_VIEW3D) {
			/* pass */
		}
		else if (t->spacetype == SPACE_IMAGE) {
			glScalef(1.0f / t->aspect[0], 1.0f / t->aspect[1], 1.0f);
		}
		else if (ELEM(t->spacetype, SPACE_IPO, SPACE_ACTION)) {
			/* only scale y */
			rcti *mask = &t->ar->v2d.mask;
			rctf *datamask = &t->ar->v2d.cur;
			float xsize = BLI_rctf_size_x(datamask);
			float ysize = BLI_rctf_size_y(datamask);
			float xmask = BLI_rcti_size_x(mask);
			float ymask = BLI_rcti_size_y(mask);
			glScalef(1.0f, (ysize / xsize) * (xmask / ymask), 1.0f);
		}

		depth_test_enabled = glIsEnabled(GL_DEPTH_TEST);
		if (depth_test_enabled)
			glDisable(GL_DEPTH_TEST);

		set_inverted_drawing(1);
		drawcircball(GL_LINE_LOOP, t->center_global, t->prop_size, imat);
		set_inverted_drawing(0);

		if (depth_test_enabled)
			glEnable(GL_DEPTH_TEST);

		glPopMatrix();
	}
}

void wmPartialViewport(rcti *drawrct, const rcti *winrct, const rcti *partialrct)
{
  /* Setup part of the viewport for partial redraw. */
  bool scissor_pad;

  if (partialrct->xmin == partialrct->xmax) {
    /* Full region. */
    *drawrct = *winrct;
    scissor_pad = true;
  }
  else {
    /* Partial redraw, clipped to region. */
    BLI_rcti_isect(winrct, partialrct, drawrct);
    scissor_pad = false;
  }

  int x = drawrct->xmin - winrct->xmin;
  int y = drawrct->ymin - winrct->ymin;
  int width = BLI_rcti_size_x(winrct) + 1;
  int height = BLI_rcti_size_y(winrct) + 1;

  int scissor_width = BLI_rcti_size_x(drawrct);
  int scissor_height = BLI_rcti_size_y(drawrct);

  /* Partial redraw rect uses different convention than region rect,
   * so compensate for that here. One pixel offset is noticeable with
   * viewport border render. */
  if (scissor_pad) {
    scissor_width += 1;
    scissor_height += 1;
  }

  glViewport(0, 0, width, height);
  glScissor(x, y, scissor_width, scissor_height);

  wmOrtho2_pixelspace(width, height);
  GPU_matrix_identity_set();
}

/* Part of the solution copied from `rect_subregion_stride_calc`. */
void GPU_select_buffer_stride_realign(const rcti *src, const rcti *dst, uint *r_buf)
{
  const int x = dst->xmin - src->xmin;
  const int y = dst->ymin - src->ymin;

  BLI_assert(src->xmin <= dst->xmin && src->ymin <= dst->ymin && src->xmax >= dst->xmax &&
             src->ymax >= dst->ymax);
  BLI_assert(x >= 0 && y >= 0);

  const int src_x = BLI_rcti_size_x(src);
  const int src_y = BLI_rcti_size_y(src);
  const int dst_x = BLI_rcti_size_x(dst);
  const int dst_y = BLI_rcti_size_y(dst);

  int last_px_id = src_x * (y + dst_y - 1) + (x + dst_x - 1);
  memset(&r_buf[last_px_id + 1], 0, (src_x * src_y - (last_px_id + 1)) * sizeof(*r_buf));

  if (last_px_id < 0) {
    /* Nothing to write. */
    BLI_assert(last_px_id == -1);
    return;
  }

  int last_px_written = dst_x * dst_y - 1;
  const int skip = src_x - dst_x;

  while (true) {
    for (int i = dst_x; i--;) {
      r_buf[last_px_id--] = r_buf[last_px_written--];
    }
    if (last_px_written < 0) {
      break;
    }
    last_px_id -= skip;
    memset(&r_buf[last_px_id + 1], 0, skip * sizeof(*r_buf));
  }
  memset(r_buf, 0, (last_px_id + 1) * sizeof(*r_buf));
}

static int actkeys_borderselect_exec(bContext *C, wmOperator *op)
{
	bAnimContext ac;
	rcti rect;
	short mode = 0, selectmode = 0;
	const bool select = !RNA_boolean_get(op->ptr, "deselect");
	const bool extend = RNA_boolean_get(op->ptr, "extend");
	
	/* get editor data */
	if (ANIM_animdata_get_context(C, &ac) == 0)
		return OPERATOR_CANCELLED;

	/* clear all selection if not extending selection */
	if (!extend) {
		deselect_action_keys(&ac, 1, SELECT_SUBTRACT);
	}
	
	/* get settings from operator */
	WM_operator_properties_border_to_rcti(op, &rect);

	if (select) {
		selectmode = SELECT_ADD;
	}
	else {
		selectmode = SELECT_SUBTRACT;
	}
	
	/* selection 'mode' depends on whether borderselect region only matters on one axis */
	if (RNA_boolean_get(op->ptr, "axis_range")) {
		/* mode depends on which axis of the range is larger to determine which axis to use 
		 *	- checking this in region-space is fine, as it's fundamentally still going to be a different rect size
		 *	- the frame-range select option is favored over the channel one (x over y), as frame-range one is often
		 *	  used for tweaking timing when "blocking", while channels is not that useful...
		 */
		if (BLI_rcti_size_x(&rect) >= BLI_rcti_size_y(&rect))
			mode = ACTKEYS_BORDERSEL_FRAMERANGE;
		else
			mode = ACTKEYS_BORDERSEL_CHANNELS;
	}
	else 
		mode = ACTKEYS_BORDERSEL_ALLKEYS;
	
	/* apply borderselect action */
	borderselect_action(&ac, rect, mode, selectmode);
	
	/* set notifier that keyframe selection have changed */
	WM_event_add_notifier(C, NC_ANIMATION | ND_KEYFRAME | NA_SELECTED, NULL);
	
	return OPERATOR_FINISHED;
}