Sdl surface pixel format. It has been slightly updated here.
May 28, 2024 · Next we have the mapRGBA() which takes in a set of red, green, blue, and alpha in 8 bits and gives us back a single 32bit pixel in the format of the internal SDL_Surface. They are carefully written to work with any depth currently supported by SDL. Every SDL2 surface has a width and height, a pixel format and other properties. Rendering pixels from array of RGB values in SDL 1. The pixel format of the created texture may be different from the pixel format of the surface. w and h are the width and height pixel: a pixel value. SDL_UnlockSurface -- Unlocks a previously locked SDL_Surface *: src: the existing SDL_Surface structure to convert. Apr 9, 2015 · The put_pixel(SDL_Surface* screen,int x,int y,pixel* p) line seems complicated. An SDL_Surface is a pixel buffer that represents an image in memory. The following two functions can be used to get and set single pixels of a surface. (SDL_Surface *) Returns the new SDL_Surface structure that is created or NULL if it fails; call SDL_GetError() for more information. SDL read pixels from texture. Each pixel occupies a number of bits appropriate for its format, with most formats representing each pixel as one or more whole bytes (in some indexed formats, instead multiple pixels are packed into each byte), and a byte order given by the format. Example: SDL_PIXELFORMAT_RGB565. Convert the pixels in surface to format, a symbol representing a specific pixel format, and return a new surface object. 0 You can also find more information on byte and bits size about the image by looking at the . SDL_GetRGB; SDL_GetRGBA; SDL_MapRGBA Nov 20, 2018 · Yet a 3rd option, if SDL_Image knows how to read your "RAW" file, is to use IMG_Load to get an SDL_Surface of your image then creating a texture from that surface using SDL_CreateTextureFromSurface Share May 15, 2019 · A given SDL_Renderer is going to support at least one SDL_PixelFormatEnum; Other formats will work but may incur a conversion penalty at creation and/or use. Return Value (SDL_Surface *) Returns the new SDL_Surface structure that is created or NULL if it fails; call SDL_GetError() for more information. SDL_CreateRGBSurface -- Create an empty SDL_Surface SDL_CreateRGBSurfaceFrom -- Create an SDL_Surface from pixel data SDL_FreeSurface -- Frees (deletes) a SDL_Surface SDL_LockSurface -- Lock a surface for directly access. SDL_BITSPERPIXEL(format) the number of bits of color information in the pixel format. Uint8: r: the red component of the pixel in the range 0-255. If you know you you will only have up to 256 distinct colors and you want to be able to switch them quickly, then it might be a good way to go. A pixel format has either a palette or masks. Uint32: dst_format: an SDL_PixelFormatEnum value of the dst pixels format. On little-endian systems the pixel is stored in memory as: Jun 14, 2018 · Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Return Value (SDL_Surface *) Returns the new SDL_Surface structure that is created or NULL if it fails; call SDL_GetError() for more information. This function operates mostly like SDL_CreateRGBSurfaceFrom(), except instead of providing pixel color masks, you provide it with a predefined format from SDL_PixelFormatEnum. 0. Allocate an empty surface (must be called after SDL_SetVideoMode). : Uint32: flags: the flags are unused and should be set to 0; this is a leftover from SDL 1. You can ask SDL to lookup the SDL_PixelFormat corresponding to the Uint32 you mentioned though: /** * Create an SDL_PixelFormat structure corresponding to a pixel format. It has been slightly updated here. SDL_PixelFormat: format: the SDL_PixelFormat for the new surface's pixel format. Aug 14, 2015 · So, SDL_PixelFormat and SDL_PixelFormatEnum are simply completely different types, you don't cast between them. Version. This function operates mostly like SDL_CreateRGBSurface(), except instead of providing pixel color masks, you provide it with a predefined format from SDL_PixelFormatEnum. Oct 29, 2023 · I'm trying to create a Gaussian blur in C using SDL. If a palette is used Rmask, Gmask, Bmask, and Amask will be 0. SDL_RenderCopy (Using Textures with SDL_SetTextureColorMod) I'm not sure what's a better approach. source pub fn convert_format ( &self, format: PixelFormatEnum , ) -> Result < Surface <'static>, String > It is a pixel of the format used by the surface, as generated by SDL_MapRGB(). If the pixel format bpp (color depth) is less than 32-bpp then the unused upper bits of the return value can safely be ignored (e. Given an “Sdl. I have some example code that does pretty much exactly what I want it to do, but I want to change the pixel color. An SDL_PixelFormat describes the format of the pixel data stored at the pixels field of an SDL_Surface. Every surface stores an SDL_PixelFormat in the format field. 8-bit pixel formats are the easiest to understand. sdl surface to opengl texture. It appeared that the color channels have been swapped, i. SDL_BYTESPERPIXEL(format) the number of bytes used to represent a pixel. How to set a pixel in a SDL_surface? 5. Nov 27, 2018 · SDL Surface Pixel Format Conversion. ) SDL_Surface. It calls SDL_ConvertSurface. This is formed into SDL_surface. . So my questions are: I have an array of uint8_t which represents a greyscale picture, where each pixel is one uint8_t. Ask Question Asked in my Terrain class where I'm preparing my vertex buffer I'm reading pixel values with this The surface is not modified or freed by this function. SDL_ISPIXELFORMAT_ALPHA(format) true Return Value (SDL_Surface *) Returns the new SDL_Surface structure that is created or NULL if it fails; call SDL_GetError() for more information. h. int: src_pitch: the pitch of the source pixels, in bytes. , but seemingly easier to implement with my current system. SDL_GetRGBA -- Get RGBA values from a pixel in the specified pixel format. typedef struct SDL_Surface { Uint32 flags; /**< Read-only */ SDL_PixelFormat *format; /**< Read-only */ int w, h; /**< Read-only */ int pitch; /**< Read-only */ void *pixels; /**< Read-write */ /** Application data associated with the surface */ void *userdata; /**< Read-write */ /** information needed for surfaces requiring locks See full list on wiki. Return a bytevector containing the raw pixel data in surface. I want to use the SDL surface to generate a texture using glTexImage2D. There are no guarantees about what format the new SDL_Surface data will be; in many cases, SDL_image will attempt to supply a surface that exactly matches the provided image, but in others it might have to convert (either because the image is in a format that SDL doesn't directly support or because it's compressed data that could reasonably Jan 28, 2024 · SDL_GetRGB() takes an offset into the pixel data. 0. Uint8 * g: a pointer filled in with the green component. mSurface = SDL_CreateRGBSurfaceFrom(mData, mWidth, mHeight, 8, mWidth, 0xFF0000, 0xFF0000, 0xFF0000, 0xFF0000); Jan 5, 2022 · SDL Surface Pixel Format Conversion. SDL_Texture * texture: the texture to update. If x and y is the function draw arguments, why are they then declared in the function indata? I should have to call put_pixel with the command put_pixel(something,x,y,something2). RLE acceleration can substantially speed up blitting of images with large horizontal runs of transparent pixels. Copying SDL_Surface pixels into an STL container. Syntax. Integer scalings only as set by function below. Set the pixel format AND create texture from surface in SDL. SDL_Surface *SDL_DisplayFormatAlpha(SDL_Surface *surface); Description This function takes a surface and copies it to a new surface of the pixel format and colors of the video framebuffer plus an alpha channel, suitable for fast blitting onto the display surface. This function is available since SDL 3. SDL_LockSurface's documentation suggests, not very clearly, that pixel format of some surfaces may change during their lifetime, and so the proper way to access a surface's pixel format would be to first check if the surface needs locking with SDL_MUSTLOCK, and if so, lock it using SDL_LockSurface. c. pixels member, you should be aware of padding bytes. Since SDL_Surface is just the raw pixel data, it is not optimized in any way and should be avoided when rendering. man SDL_Surface (3): SDL_Surface's represent areas of "graphical" memory, memory that can be drawn to. I’m using the Tsdl library, and it seems to have two types to work with SDL formats. 1. const SDL_Rect * rect: an SDL_Rect structure representing the area to update, or NULL to update the entire texture. Dec 15, 2022 · SDL_SetRenderTarget(renderer, target); render your textures rotated, flipped, translated using SDL_RenderCopyEx SDL_RenderReadPixels(renderer, rect, format, pixels, pitch); With the last step you read the pixels from the render target using SDL_RenderReadPixels and then you have to figure out if the alpha channel of the desired pixel is Aug 7, 2018 · The SDL2 Surface. Learn more Explore Teams Copies the surface into a new one that is optimized for blitting to a surface of a specified pixel format. SDL_Surface * surface: the surface to use for the pixel format and palette. (This is the documentation for SDL3, which is under heavy development and the API is changing! SDL2 is the current stable version!) SDL_ConvertSurface. Uint8 * b: a pointer filled in with the blue component. If i use say x=56 and y= 567, aren't they resetted to 0 when declared in the parentesis? Jul 3, 2018 · Not sure why the SDL_GetWindowSurface is returning a surface with an unknown pixel format. One solution is to use the OpenGL renderer which supports NV12 pixel format. Every surface stores a SDL_PixelFormat in the format field. If depth is greater than 8 bits, the pixel format is set using the [RGBA]mask parameters. SDL_Init(SDL_INIT_VIDEO); /* scale here to make the window larger than the surface itself. Outputs: Window pixel format SDL_PIXELFORMAT_RGB888 Surface pixel format SDL_PIXELFORMAT_UNKNOWN Code Nov 9, 2015 · This article was originally posted on 13th February 2014 at Programmer’s Ranch. g. The source code for this article is available at the Gigi Labs BitBucket repository. Apr 29, 2014 · To access an SDL_Texture's pixels, you must create a blank texture using SDL_CreateTexture() and pass in SDL_TEXTUREACCESS_STREAMING for the access parameter, then copy the pixels of a surface into it. If flag is SDL_SRCCOLORKEY then key is the transparent pixel value in the source image of a blit. I would like to display this in a window using the SDL2 library. I assume its referring to the last four arguments in the SDL_CreateRGBSurface function, but I don't know what could be I am currently trying some things using pixel manipulation and I would like to set the pixel format of a SDL_Surface. Oct 3, 2017 · I created a bmp and I load it using SDL_LoadBMP when inspecting the generated SDL_Surface I can see it is of format SDL_PIXELFORMAT_INDEX8. Feb 18, 2012 · SDL_SetPalette() is only for use in 8-bit palleted surfaces. int: pitch: the number of bytes between each row, including padding. This function takes a surface and copies it to a new surface of the pixel format and colors of the video framebuffer, suitable for fast blitting onto the display surface. Feb 10, 2014 · It prints "SURFACE ERROR Unknown pixel format". The pixel is described by the format field, which tells us, how the pixel is organized in SDL_Surface *: src: the existing SDL_Surface structure to convert. org src: the existing SDL_Surface structure to convert: pixel_format: the SDL_PixelFormatEnum that the new surface is optimized for: flags: the flags are unused and should be set to 0; this is a leftover from SDL 1. Uint8: a: the alpha component of the pixel in the range 0-255. c: pitch = surface->w * surface->format->BytesPerPixel if it's a 32-bit format. First, as you've shown in the code snippet, note that screen->pixels is a pointer to the pixel data of the surface. 2's API Jan 13, 2017 · According to keltar's comment, SDL_PIXELFORMAT_NV12 requires an hardware acceleration. : const SDL_PixelFormat *: fmt: the SDL_PixelFormat structure that the new surface is optimized for. Not all surfaces require locking. main. e. All the usual SDL locking rules apply, so the pixels member of your SDL_Surface needs to be valid and stay put for the lifetime of the cairo surface. Once that's done, you can use the SDL_LockTexture() function to retrieve a pointer to the pixel data which can then be accessed and modified. Aug 6, 2022 · After a long time away, I'm coming back to SDL, using version SDL2. How can I do that? I've read about SDL_ConvertSurface() in the documentation, but I can't figure out, how to put it together. color should be a pixel of the format used by the surface, and can be generated by SDL_MapRGB() or SDL_MapRGBA(). Between calls to SDL_LockSurface() / SDL_UnlockSurface(), you can write to and read from surface->pixels, using the pixel format stored in surface->format. I'd like to get it working this way at least just for the Mar 20, 2021 · This code gives the byte offset to the pixel at coordinates x, y: (formattedImage->pitch * y) + (x * bpp) But you're providing it as the index into an array to which you've assigned the type Uint32*: Feb 21, 2015 · SDL Surface Pixel Format Conversion. 2 Set the pixel format AND create Oct 23, 2015 · Use OpenGL to do the pixel manipulation directly on the GPU, which some forums tells me that this is way slower than my current approach as "this is not how a GPU works" Don't store a pixel array, store a BMP in RAM directly, manipulate that and then move it to an SDL_Surface or SDL_Texture The memory layout of a packed pixel format depends on system endianness. The SDL2 surface allows you to represent graphic objects like sprites. Mar 23, 2021 · The reason why the bpp doesn't match is that the SDL_UpdateTexture accesses the surface data (pixels) without even looking at the pixel format and SDL_CreateTextureFromSurface creates a texture compatible with the renderer, not caring about the surface format. SDL2 Rendering to texture. Uint8 * a: a pointer filled in with the alpha component. Drawing a rectangle on SDL_Surface pixels. You also need to keep in mind that each pixel in this image is 4 bytes (bitDepth = 32 and Bpp = 4). const SDL_PixelFormat * format: an SDL_PixelFormat structure describing the format of the pixel. Nevertheless, it is a concept which originates from the outdated SDL 1. the channel bit pattern of the pixel format; see Remarks for details. See SDL_SetSurfaceRLE() for details. Jun 2, 2015 · I've tried using SDL_ConvertSurfaceFormat but surface->format->BitsPerPixel stays at 32. If depth is 8 bits an empty palette is allocated for the surface, otherwise a 'packed-pixel' SDL_PixelFormat is created using the [RGBA]mask's provided (see SDL_PixelFormat). 2. Oct 29, 2018 · Look at SDL_CalculatePitch in SDL_pixels. If you wish to do pixel level modifications on a surface, then Dec 2, 2010 · I want to convert an SDL_Surface, which was loaded by IMG_Load() to an other pixel format (rgba8) for an OpenGL Texture. The problem here is that I am loading up an image with the SDL_image. And my answer addresses the fact that it depends on the format. map_rgb: pixel_format → uint8 → uint8 → uint8 → uint32 I need its “pixel_format Drawing Directly to the Display. Once you are done accessing the surface, you should use SDL_UnlockSurface to release it. Greetings! 🙂 In “Handling Keyboard and Mouse Events in SDL2“, we saw how we could handle keyboard and mouse events to allow the … Continue reading SDL2 Pixel Drawing → Jul 19, 2018 · In the code, I open both a DirectX window and an SDL window and then verify the pixel format of both. If you want to take advantage of hardware colorkey or alpha blit acceleration, you should set the colorkey and alpha value before calling this Manipulating the contents of screen->pixels will modify pixels, with a couple of caveats. 1 openGL texture from SDL Surface. SDL_Surface. Valid format types are: index1lsb (This is the documentation for SDL3, which is under heavy development and the API is changing! SDL2 is the current stable version!) SDL_CreateSurface. Procedure: surface-pixel-format surface. The video framebuffer is returned as a SDL_Surface by SDL_SetVideoMode and SDL_GetVideoSurface . If the color value contains an alpha component then the destination is simply filled with that alpha information, no blending takes place. SDL_ISPIXELFORMAT_INDEXED(format) true for pixel formats that have a palette. SDL_PROP_WINDOW_CREATE_WIN32_PIXEL_FORMAT_HWND_POINTER: optional, another window to share pixel format with, useful for OpenGL windows These are additional supported properties with X11: SDL_PROP_WINDOW_CREATE_X11_WINDOW_NUMBER : the X11 Window associated with the window, if you want to wrap an existing window. I have tried to create an SDL_Surface from the array by doing. 0 still uses SDL_Texture ( like image loading or text rendering ) Return Value (Uint32) Returns the pixel format of the window on success or SDL_PIXELFORMAT_UNKNOWN on failure; call SDL_GetError() for more information. I expect this code to display an entirely red window, but instead I'm getting an all black window. If depth is 4 or 8 bits, an empty palette is allocated for the surface. Use SDL_GetRendererInfo() to populate a SDL_RendererInfo & use one of the formats in SDL_RendererInfo::texture_formats (from here): Apr 21, 2024 · In SDL2, SDL_Renderer and SDL_Surface are two different ways to render graphics, each with its own use cases and advantages. Allows any pixel-format (Display surface) SDL_HWPALETTE: Surface has exclusive palette: SDL_DOUBLEBUF: Surface is double buffered (Display surface) SDL_FULLSCREEN: Surface is full screen (Display Surface) SDL_OPENGL: Surface has an OpenGL context (Display Surface) SDL_OPENGLBLIT: Surface supports OpenGL blitting (Display Surface) SDL_RESIZABLE An SDL_Surface is basically a struct that contains all the raw pixel data along with some meta-information like size and pixel format. Once you are done accessing the surface, you should use SDL_UnlockSurface() to release it. You can manipulate the pixels directly and perform software-based rendering using an SDL SDL_Surface *: src: the existing SDL_Surface structure to convert. (This is the legacy documentation for stable SDL2, the current stable version; SDL3 is the current development version. image = SDL_ConvertSurfaceFormat(image, SDL_PIXELFORMAT_ARGB8888, 0); What this does is take our surface (in this case the one that image points to) and return an equivalent surface with the pixel format we specify. int: pitch: the number of bytes in a row of pixel data, including padding between lines. int: dst_pitch: the pitch of the Mar 11, 2019 · A surface created with SDL_PIXELFORMAT_INDEX1MSB is one-bit-per-pixel. See Also. Most of the fields should be pretty obvious. Returns the human readable name of the specified pixel format or SDL_PIXELFORMAT_UNKNOWN if the format isn't recognized. Procedure: convert-surface-format surface format. Some parts of SDL2. openGL texture from SDL Surface. Remarks. 0 SDL2 texture's pixel format and surface color mask . And only when you are done making your edits, convert the SDL_Surface to a SDL_Texture using the SDL_CreateTextureFromSurface function. Still, there are reasons why we need to introduce it here. The video framebuffer is returned as a SDL_Surface by SDL_SetVideoMode and SDL_GetVideoSurface. format field (It's a SDL_PixelFormat*, which lets you access stuff like how many bytes per pixel you have there). Quote: mr_tawan wrote: I think you should lock the surface before the whole loop, and unlock it after the whole loop. So I ha the width of the surface. Uint8: b: the blue component of the pixel in the range 0-255. The pixel is represented by a 16-bit value, with R in bits 11-15, G in bits 5-10 and B in bits 0-4. A SDL_PixelFormat describes the format of the pixel data stored at the pixels field of a SDL_Surface. int: height: the height of the surface. Here is my function: We admit that the param surface is a grayscale image (that's why i only use the r). Jul 1, 2012 · The problem with your png image is more likely caused by the png being 32-bits per pixel. The 1 and 0 are indexed to colors you can set. SDL_ISPIXELFORMAT_ALPHA(format) true SDL_Surface 's represent areas of "graphical" memory, memory that can be drawn to. Sep 25, 2013 · SDL Surface Pixel Format Conversion. SDL2 texture's pixel format and surface color mask. libsdl. Allocate a new surface with a specific pixel format. Feb 11, 2018 · The SDL_Surface structure has a field named pixels which is an array containing every pixel from left to right, top to bottom, using some pixel format (given by the field format). SDL_PixelFormat * format: the format of the pixels stored in the surface; see SDL_PixelFormat for details (read-only) int : w, h: the width and height in pixels (read-only) int : pitch: the length of a row of pixels in bytes (read-only) void* pixels: the pointer to the actual pixel data; see Remarks for details (read-write) void* userdata Nov 4, 2017 · @EmZee But you already do read from a surface, when you do memcpy() of pixels from the surface into your locked texture, so I think @keltar has a point: there is no reason for you to bother with creating a texture (which you forgot to free, by the way) at all, when you could simply read the needed pixel value from original surface's pixels. Return the pixel format for surface. How to change RGB values in SDL surface? 1. How do you access pixels directly? The SDL_Surface struct has a "pixels" member, but it's defined as a void*, which really doesn't provide much useful data, and I can't seem to find any tutorials on how it works. Probably the best solution for you is to inspect the format field of the SDL surface to determine to appropriate flags/values to pass to glTexImage2D. It contains the pixel data and format information. The SDL_TextureAccess hint for the created texture is SDL_TEXTUREACCESS_STATIC. const void * src: a pointer to the source pixels. 3. So, setting hint as follow: SDL_SetHint(SDL_HINT_RENDER_DRIVER, "opengl"); and setting SDL_RENDERER_ACCELERATED flag to SDL_CreateRenderer function does the trick. I had to set GL_BGRA as a pixel format parameter in glTexImage2D(). 0 Return Value (SDL_Surface *) Returns the new SDL_Surface structure that is created or NULL if it fails; call SDL_GetError() for more information. Between calls to SDL_LockSurface and SDL_UnlockSurface, you can write to and read from surface->pixels, using the pixel format stored in surface->format. Mar 28, 2010 · Here's our functions to get and put pixels. #2 is probably easier as I have a whole system built around fast texture rendering (not necessarily faster than 1. Sep 20, 2021 · First have a look at SDL_Surface. If flag is OR'd with SDL_RLEACCEL then the surface will be draw using RLE acceleration when drawn with SDL_BlitSurface. const void * pixels: the raw pixel data in the format of the texture. In terms of data members we have a pointer to the surface that holds our pixels. Description. 2 and therefore should not be used anymore. The parts you're interested in: SDL_PixelFormat*format; int w, h; int pitch; void *pixels; What else you should know: On position x, y (which must be greater or equal to 0 and less than w, h) the surface contains a pixel. Copy an existing surface to a new surface of the specified format. Feb 27, 2015 · SDL Surface Pixel Format Conversion. Jan 7, 2016 · Weird SDL_Surface->format->BytesPerPixel value. Otherwise, you need to lock the surface beforehand and unlock it afterwards, using SDL (SDL_Surface *) Returns the new SDL_Surface structure that is created or NULL if it fails; call SDL_GetError() for more information. void * pixels: a pointer to existing pixel data. SDL_Surface 's represent areas of "graphical" memory, memory that can be drawn to. There are no guarantees about what format the new SDL_Surface data will be; in many cases, SDL_image will attempt to supply a surface that exactly matches the provided image, but in others it might have to convert (either because the image is in a format that SDL doesn't directly support or because it's compressed data that could reasonably Apr 7, 2016 · Running on OS X, I've loaded a texture in OpenGL using SDL_Image library (using IMG_LOAD() which returns SDL_Surface*). Mar 9, 2018 · Your problem is in the way you extract pixel from surface: Uint8 pixel = p[(y * surface->w) + x]; You assume that each pixel takes one byte (could be verified by inspecting surface->format->BytesPerPixel), and that each row is surface->w*1 bytes long - but it isn't. 2? 4. Uint8: g: the green component of the pixel in the range 0-255. 2's API. 7. SDL's 32 bit pixel formats with per pixel alpha are not supported directly by cairo because cairo and SDL disagree on the interpretation of pixel values with alpha: SDL uses unpremultiplied pixels Return Value. If you're copying pixel data directly through an SDL_Surface . Apr 17, 2022 · Now available on Stack Overflow for Teams! AI features where you work: search, IDE, and chat. SDL_LockSurface sets up a surface for directly accessing the pixels. : Uint32: pixel_format: the SDL_PixelFormatEnum that the new surface is optimized for. If you wish to do pixel level modifications on a surface, then understanding how SDL stores its color information is essential. In case you missed the bitmap font tutorial, here's a quick review on how pixel access works: First thing we do is convert the pixel pointer from type void to 32bit integer so we can properly access them. void * dst: a pointer to be filled in with new pixel data. The key must be of the same pixel format as the surface, SDL_MapRGB is often useful for obtaining an acceptable value. A collection of pixels used in software blitting. SDL_Surface *: src: the existing SDL_Surface structure to convert. 6. I'm able to get it working if I directly write to window_surface with the same technique, but not by blitting another surface. Aug 19, 2019 · Hi, I’m trying to learn OCaml and the SDL graphics library simultaneously at the moment, and I’m still struggling with how to eat my way through an OCaml API. The surface is not modified or freed by this function. , with a 16-bpp format the return value can be assigned to a Uint16, and similarly a Uint8 for an 8-bpp format). You can directly modify this pixel array if SDL_MUSTLOCK(surface) is false. c Code: /* Public routines */ /* * Create an empty RGB surface of the appropriate depth */ SDL_Surface * SDL_CreateRGBSurface(Uint32 flags, int width, int height, int depth, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask) { SDL_Surface *surface; Uint32 format; /* The flags are no longer used, make the SDL_Surface * surface: the surface to use for the pixel format and palette. Get pixel info from SDL2 texture. Every surface stores a SDL_PixelFormat in the format field. SDL_BlitSurface; SDL_GetColorKey Mar 29, 2023 · This is what you should focus on: if you want to edit pixel data or do any sort of modification to something that you then plan to render on screen, then do it in an SDL_Surface. surface”, to use the function Sdl. SDL_Surface* gaussian_blur(SDL_Surface* Apr 22, 2021 · I'd like to directly modify pixels in my window in SDL 2. Uint8 * r: a pointer filled in with the red component. Remarks. Use SDL_QueryTexture() to query the pixel format of the texture. Drawing Directly to the Display. 11. So on the same machine in the same program DirectX returns an ARGB8888 window but SDL2 returns an RGB888 window. I have two pixes stored in a 32 bit unsigned integer (4 bytes per pixel, using SDL's types for convenience): Uint32 pixel1; // Source pixel, format: SDL_PIXELFORMAT_BGRA8888 Uint32 src_format: an SDL_PixelFormatEnum value of the src pixels format. If you're worrying about surface ->w changed in the loop, you can copy the value to another variable before the loop. ) #1 seems ideal because it's in the SDL2 library for a reason I'd think void set_pixel(SDL_Surface *surface, int x, int y, Uint32 pixel) { Uint32 * const target_pixel = (Uint32 *) ((Uint8 *) surface->pixels + y * surface->pitch + x * surface->format->BytesPerPixel); *target_pixel = pixel; } Draws a diagonal red line pixel by pixel on the screen using SDL_RenderDrawPoint. This function is available since SDL 2. kgqtfijmpjadvltlhryalymwkkpegnqqrpqxuodocfytuksxszjh
Sdl surface pixel format. Allocate a new surface with a specific pixel format.
Sdl surface pixel format. int: src_pitch: the pitch of the source pixels, in bytes.