I'm working with a facetgrid pointplot graph, and have a palette of four colors. They keep drawing lightest to darkest, so dark always covers light. How do I control which color is first drawn? (Sometimes I want the medium toned on top, other times light, etc.)
EDIT
For an MVE:
g = sns.FacetGrid(tips, col="time", hue="smoker")
g = (g.map(plt.scatter, "total_bill", "tip", edgecolor="w").add_legend())
from https://seaborn.pydata.org/generated/seaborn.FacetGrid.html
I can't share my data and it's time consuming to exactly replicate it, this is similar enough.
Related
I have this plot as part of a PySide program;
And there are two problems I have with it. The first is the ugly grey border. I know I can can get rid of it using the toolbar option, but I can't find a way to it programatically, or make it default to that when it plots...
The second issue, is that it is drawing the grid lines on top of the surface, which I would rather it didn't do... How do I get the grid lines to be drawn underneath the surface?
EDIT:
i'm using version 1.1.1;
this doesn't happen for all plot types - i.e.
that is fine.
If i try and plot multiple objects, then it can be a problem;
but i understand that's a limitation of mplot3d not being a try 3D engine, just a set of 3D images with a Z-Ordering, so the order of objects drawn becomes orientation dependant. (same graph - different angle: enter link description here).
The grid lines should surely always be at the bottom of the drawing though, no? Is there a way to force them to be?
Will.
I am using OpenGL ES 1.1 to draw lines in my iPad app. I want to make sure that the drawn lines are always visible on the screen regardless of the background colors, and without allowing the user to choose a color. Is there a blend function that will create this effect? So the color of the line drawn will change based on the colors already drawn beneath it and therefore always be visible.
Sadly the final blending of fragments into the framebuffer is still fixed function. Furthermore glLogicOp isn't implemented in ES so you can't do something cheap like XOR drawing.
I think the net effect is that:
you want the output colour to be a custom function of the colour already in the frame buffer;
but the frame buffer can't be read in a shader (it'd break the pipeline and lead towards concurrency issues).
You're therefore going to have to implement a ping pong pipeline.
You have two off-screen buffers. One represents what you output last frame, the other represents what you output the frame before that.
To generate a new frame you render using the one that represents the frame before as an input. Because it's an input you can sample it wherever you want and make whatever calculations you like on it. You render to the other buffer that you have (ie, the even older one) because you no longer care about its contents.
Then you copy all that to the screen and swap the two over, meaning that what you just drew is still in a texture to refer to as what you drew last frame. What you just referred to becomes your next drawing target because it's something you conveniently already have lying around.
So you'll be immediately interested in rendering to a texture. You'll also need to decide what function you want to use to pick a suitable 'different' colour to the existing background. Maybe just inverting it will do?
I think this could work:
glBlendFunc(GL_ONE_MINUS_DST_COLOR, GL_ZERO);
Draw your lines with a white color, and then the result will be rendered as
[1,1,1,1] * ( 1 - [DstR, DstG, DstB, DstA]) + ([DstR, DstG, DstB, DstA] * 0)
This should render a black pixel where the background is white, a white pixel where the background is black, a yellow pixel where the background is blue, etc.
I have a layer with a sprite of a simple black donut. I want the user to be able to draw on the sprite in a different color (which I've managed to do without any problem using CCRenderTexture).
My question is how I can calculate whether the image has been traced at least 95% (meaning, find out when 95% of the black pixels are now the new color). I've tried methods like taking a screenshot of the layer and counting the number of black pixels, but it hasn't worked that well (using this solution: https://stackoverflow.com/a/1262893/1577738).
It would be even better if I could just change the color of each pixel as it's touched (to avoid issues with coloring out of the lines). I could theoretically just split the donut into like 10 sprites and change that section's color if the user touches it, but that seems ridiculous if I give the user options to use a bunch of different colors.
Am I going about this the wrong way? Your suggestions are much appreciated!
Reading pixel colors will be rather inaccurate and slow. I suggest dividing the area into smaller rectangles (ie 8x8 or 4x4) and then flag each as "visited" when the user draws on it. If most rectangle areas are flagged, the user has drawn on most parts of the texture.
I'm using Core Plot to graph linear equations.
I would like to be able to supply two different data points and have a line drawn between them, but also extrapolated beyond the points themselves so that the line extends all the way to the edges of the plot area.
For example, given a 20x20 plot area with the origin centered and points at -5,-5 and 5,5, the line (green below) would extend all the way from -10,10 to 10,10 (blue below).
Is this possible? Is the best option just to find the plot range (which will be different each time) and find two points that are outside of it? I'm not sure if this will work; I have user interaction enabled and I want to make sure that the user can't accidentally pan far enough that the line will end.
Your idea of finding two endpoints outside the plot range is what I'd do. If you've limited the scrolling range, just pick points at the limits of that range. If not, you'll need to monitor changes to the plot space ranges with a plot space delegate and update the plot as needed.
I have a Core-Plot Graph within a Mac Application. But the inside table is appearing shifted down and to the left of the containing "frame/border" so that neither of the axis' are showing. I cannot figure out how to change this does anyone know what parameters I need to change to fix this?
Update: Sorry I did not realize I could upload an image, I have done so know and will try your suggestions in the mean-time.
Not sure what you mean by "inside table". It would be easier to offer suggestions if you could post a screenshot.
Without seeing what's wrong, here are some common areas to look at:
If you haven't already done so, look at the example apps included with Core Plot for ideas. The Plot Gallery app has many sample plots and the others are useful, too.
You may need to add padding (paddingLeft, paddingBottom, etc.) on the graph and/or plot area frame. Padding the graph pushes everything in away from the edges of the graph. Padding the plot area frame pushes the plot area in so the axes and titles can hang outside the plot area (the area where the plots are drawn).
If you want to keep an axes pinned to a specific place, e.g., the edge of the graph, set up a floating axis. Otherwise make sure the orthogonal coordinate is set (it defaults to 0). For example, the orthogonal coordinate for the x-axis is the y-value where the x-axis crosses the y-axis.