diff options
Diffstat (limited to 'src/rtextures.c')
| -rw-r--r-- | src/rtextures.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/src/rtextures.c b/src/rtextures.c index e914db41..9d547cd0 100644 --- a/src/rtextures.c +++ b/src/rtextures.c @@ -1630,6 +1630,208 @@ Image ImageTextEx(Font font, const char *text, float fontSize, float spacing, Co return imText; } +// Create an image from a selected channel of another image +Image ImageFromChannel(Image image, int selectedChannel) +{ + Image result = { 0 }; + + // Security check to avoid program crash + if ((image.data == NULL) || (image.width == 0) || (image.height == 0)) + return result; + + // Check selected channel + if (selectedChannel < 0) + { + TRACELOG(LOG_WARNING, "Channel cannot be negative. Setting channel to 0."); + selectedChannel = 0; + } + if (image.format == PIXELFORMAT_UNCOMPRESSED_GRAYSCALE + || image.format == PIXELFORMAT_UNCOMPRESSED_R32 + || image.format == PIXELFORMAT_UNCOMPRESSED_R16 + ) + { + if (selectedChannel > 0) + { + TRACELOG(LOG_WARNING, "This image has only 1 channel. Setting channel to it."); + selectedChannel = 0; + } + } + else if (image.format == PIXELFORMAT_UNCOMPRESSED_GRAY_ALPHA) + { + if (selectedChannel > 1) + { + TRACELOG(LOG_WARNING, "This image has only 2 channels. Setting channel to alpha."); + selectedChannel = 1; + } + } + else if (image.format == PIXELFORMAT_UNCOMPRESSED_R5G6B5 + || image.format == PIXELFORMAT_UNCOMPRESSED_R8G8B8 + || image.format == PIXELFORMAT_UNCOMPRESSED_R32G32B32 + || image.format == PIXELFORMAT_UNCOMPRESSED_R16G16B16 + ) + { + if (selectedChannel > 2) + { + TRACELOG(LOG_WARNING, "This image has only 3 channels. Setting channel to red."); + selectedChannel = 0; + } + } + + // formats rgba + if (selectedChannel > 3) + { + TRACELOG(LOG_WARNING, "ImageFromChannel supports channels 0 to 3 (rgba). Setting channel to alpha."); + selectedChannel = 3; + } + + result.format = PIXELFORMAT_UNCOMPRESSED_GRAYSCALE; + result.height = image.height; + result.width = image.width; + result.mipmaps = 1; + + unsigned char *pixels = (unsigned char *)RL_CALLOC(image.width * image.height, sizeof(unsigned char)); // values 0 to 255 + + if (image.format >= PIXELFORMAT_COMPRESSED_DXT1_RGB) TRACELOG(LOG_WARNING, "IMAGE: Pixel data retrieval not supported for compressed image formats"); + else + { + for (int i = 0, k = 0; i < image.width * image.height; ++i) + { + float imageValue = -1; + switch (image.format) + { + case PIXELFORMAT_UNCOMPRESSED_GRAYSCALE: + { + imageValue = (float)((unsigned char *)image.data)[i + selectedChannel]/255.0f; + + } break; + case PIXELFORMAT_UNCOMPRESSED_GRAY_ALPHA: + { + imageValue = (float)((unsigned char *)image.data)[k + selectedChannel]/255.0f; + + k += 2; + } break; + case PIXELFORMAT_UNCOMPRESSED_R5G5B5A1: + { + unsigned short pixel = ((unsigned short *)image.data)[i]; + + if (selectedChannel == 0) + { + imageValue = (float)((pixel & 0b1111100000000000) >> 11)*(1.0f/31); + } + else if (selectedChannel == 1) + { + imageValue = (float)((pixel & 0b0000011111000000) >> 6)*(1.0f/31); + } + else if (selectedChannel == 2) + { + imageValue = (float)((pixel & 0b0000000000111110) >> 1)*(1.0f/31); + } + else if (selectedChannel == 3) + { + imageValue = ((pixel & 0b0000000000000001) == 0)? 0.0f : 1.0f; + } + + } break; + case PIXELFORMAT_UNCOMPRESSED_R5G6B5: + { + unsigned short pixel = ((unsigned short *)image.data)[i]; + + if (selectedChannel == 0) + { + imageValue = (float)((pixel & 0b1111100000000000) >> 11)*(1.0f/31); + } + else if (selectedChannel == 1) + { + imageValue = (float)((pixel & 0b0000011111100000) >> 5)*(1.0f/63); + } + else if (selectedChannel == 2) + { + imageValue = (float)(pixel & 0b0000000000011111)*(1.0f/31); + } + + } break; + case PIXELFORMAT_UNCOMPRESSED_R4G4B4A4: + { + unsigned short pixel = ((unsigned short *)image.data)[i]; + + if (selectedChannel == 0) + { + imageValue = (float)((pixel & 0b1111000000000000) >> 12)*(1.0f/15); + } + else if (selectedChannel == 1) + { + imageValue = (float)((pixel & 0b0000111100000000) >> 8)*(1.0f/15); + } + else if (selectedChannel == 2) + { + imageValue = (float)((pixel & 0b0000000011110000) >> 4)*(1.0f/15); + } + else if (selectedChannel == 3) + { + imageValue = (float)(pixel & 0b0000000000001111)*(1.0f/15); + } + + } break; + case PIXELFORMAT_UNCOMPRESSED_R8G8B8A8: + { + imageValue = (float)((unsigned char *)image.data)[k + selectedChannel]/255.0f; + + k += 4; + } break; + case PIXELFORMAT_UNCOMPRESSED_R8G8B8: + { + imageValue = (float)((unsigned char *)image.data)[k + selectedChannel]/255.0f; + + k += 3; + } break; + case PIXELFORMAT_UNCOMPRESSED_R32: + { + imageValue = ((float *)image.data)[k]; + + k += 1; + } break; + case PIXELFORMAT_UNCOMPRESSED_R32G32B32: + { + imageValue = ((float *)image.data)[k + selectedChannel]; + + k += 3; + } break; + case PIXELFORMAT_UNCOMPRESSED_R32G32B32A32: + { + imageValue = ((float *)image.data)[k + selectedChannel]; + + k += 4; + } break; + case PIXELFORMAT_UNCOMPRESSED_R16: + { + imageValue = HalfToFloat(((unsigned short *)image.data)[k]); + + k += 1; + } break; + case PIXELFORMAT_UNCOMPRESSED_R16G16B16: + { + imageValue = HalfToFloat(((unsigned short *)image.data)[k+selectedChannel]); + + k += 3; + } break; + case PIXELFORMAT_UNCOMPRESSED_R16G16B16A16: + { + imageValue = HalfToFloat(((unsigned short *)image.data)[k + selectedChannel]); + + k += 4; + } break; + default: break; + } + + pixels[i] = imageValue * 255; + } + } + + result.data = pixels; + + return result; +} + // Resize and image to new size using Nearest-Neighbor scaling algorithm void ImageResizeNN(Image *image,int newWidth,int newHeight) { |