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//*****************************************************************************/ // // File name: AlphaBlending.cpp // Location: See Matrox Example Launcher in the MIL Control Center // // // Synopsis: This program demonstrates how to combine MimArithMultiple and // MbufClearCond to create a constant alpha-blended overlay. // // Copyright (C) Matrox Electronic Systems Ltd., 1992-2016. // All Rights Reserved #include <mil.h> /**************************************************************************** Example description. ****************************************************************************/ void PrintHeader() { MosPrintf(MIL_TEXT("[EXAMPLE NAME]\n") MIL_TEXT("AlphaBlending\n\n") MIL_TEXT("[SYNOPSIS]\n") MIL_TEXT("This program demonstrates how to combine MimArithMultiple and \n") MIL_TEXT("MbufClearCond to create a constant alpha-blended overlay.\n\n") MIL_TEXT("[MODULES USED]\n") MIL_TEXT("Modules used: application, system, display, buffer,\n") MIL_TEXT("graphic, image processing.\n\n")); MosPrintf(MIL_TEXT("Press <Enter> to continue.\n\n")); MosGetch(); } //***************************************************************************** // Constants. //***************************************************************************** // Target MIL image file specifications. static MIL_CONST_TEXT_PTR COLOR_IMAGE_FILE = M_IMAGE_PATH MIL_TEXT("BaboonRGB.mim"); static MIL_CONST_TEXT_PTR ALPHA_OVERLAY_IMAGE = M_IMAGE_PATH MIL_TEXT("imaginglogo.mim"); // Transparent color of the overlay image. static const MIL_INT USER_TRANSPARENT_COLOR = M_COLOR_WHITE; // Alpha blending value. static const MIL_INT INITIAL_ALPHA_VALUE = 160; static const MIL_INT ALPHA_INCREMENT = 5; // Graphic list color palette definitions. static const MIL_INT COLOR_SPACING = 5; static const MIL_INT SQUARE_SIZE = 50; static const MIL_INT NB_COLORS = 5; static const MIL_INT PALETTE_COLORS[NB_COLORS] = { M_RGB888(192, 0, 0), M_RGB888(0, 192, 0), M_RGB888(0, 0, 192), M_RGB888(192, 0, 192), M_RGB888(192, 192, 0) }; // Size of the brush. static const MIL_INT BRUSH_RADIUS = 5; //***************************************************************************** // Callback structure. //***************************************************************************** struct SHookData { MIL_ID MilDisplay; MIL_ID MilGraContext; MIL_ID MilGraList; MIL_ID MilDisplayedImage; MIL_ID MilOverlay; MIL_ID MilUserOverlay; MIL_INT DrawingColor; MIL_INT OverlayTransparentColor; MIL_INT Alpha; MIL_INT MinusAlphaLabel; MIL_INT PlusAlphaLabel; }; //***************************************************************************** // Function prototypes. //***************************************************************************** void AlphaBlend(MIL_ID MilDisplayedImage, MIL_ID MilOverlay, MIL_ID MilUserOverlay, MIL_INT UserTransparentColor, MIL_INT OverlayTransparentColor, MIL_INT Alpha); void DrawAlphaString(MIL_ID MilGraContext, MIL_ID MilGraList, MIL_INT Alpha); MIL_INT MFTYPE MouseMove(MIL_INT HookType, MIL_ID MilEvent, void *pUserData); MIL_INT MFTYPE GraphicSelected(MIL_INT HookType, MIL_ID MilEvent, void *pUserData); //***************************************************************************** // Main. //***************************************************************************** int MosMain(void) { // Print Header. PrintHeader(); // Allocate defaults. MIL_ID MilApplication = MappAlloc(M_DEFAULT, M_NULL); MIL_ID MilSystem = MsysAlloc(M_DEFAULT, M_SYSTEM_DEFAULT, M_DEFAULT, M_DEFAULT, M_NULL); MIL_ID MilDisplay; MdispAlloc(MilSystem, M_DEFAULT, MIL_TEXT("M_DEFAULT"), M_WINDOWED, &MilDisplay); // Allocate a graphic context. MIL_ID MilGraContext = MgraAlloc(MilSystem, M_NULL); // Restore the color image and get its size. MIL_ID MilImage = MbufRestore(COLOR_IMAGE_FILE, MilSystem, M_NULL); MIL_INT ColorImageSizeX = MbufInquire(MilImage, M_SIZE_X, M_NULL); MIL_INT ColorImageSizeY = MbufInquire(MilImage, M_SIZE_Y, M_NULL); // Select to display. MdispSelect(MilDisplay, MilImage); // Allocate an image that has the same size as the source image and // clear it with the user's transparent color. MIL_ID MilUserOverlay = MbufAllocColor(MilSystem, 3, ColorImageSizeX, ColorImageSizeY, 8 + M_UNSIGNED, M_IMAGE + M_PROC + M_BGR32 + M_PACKED, M_NULL); MbufClear(MilUserOverlay, (MIL_DOUBLE)USER_TRANSPARENT_COLOR); // Load the overlay image into the cleared buffer. MIL_INT AlphaImageSizeX = MbufDiskInquire(ALPHA_OVERLAY_IMAGE, M_SIZE_X, M_NULL); MIL_INT AlphaImageSizeY = MbufDiskInquire(ALPHA_OVERLAY_IMAGE, M_SIZE_Y, M_NULL); MIL_ID MilTransparentImageChild = MbufChild2d(MilUserOverlay, ColorImageSizeX - AlphaImageSizeX, 0, AlphaImageSizeX, AlphaImageSizeY, M_NULL); MbufLoad(ALPHA_OVERLAY_IMAGE, MilTransparentImageChild); MbufFree(MilTransparentImageChild); // Get the true overlay image. MIL_ID MilOverlay = MdispInquire(MilDisplay, M_OVERLAY_ID, M_NULL); MIL_INT OverlayTransparentColor = MdispInquire(MilDisplay, M_TRANSPARENT_COLOR, M_NULL); // Perform the alpha-blending between the overlay image and the image. AlphaBlend(MilImage, MilOverlay, MilUserOverlay, USER_TRANSPARENT_COLOR, OverlayTransparentColor, INITIAL_ALPHA_VALUE); // Print message. MosPrintf(MIL_TEXT("The user overlay image has been alpha blended with the displayed\n") MIL_TEXT("image. Only the non-transparent pixels have been copied on the\n") MIL_TEXT("display's overlay.\n\n") MIL_TEXT("Press <Enter> to continue.\n\n")); MosGetch(); // Allocate a graphic list. MIL_ID MilGraList = MgraAllocList(MilSystem, M_DEFAULT, M_NULL); // Create the brush and color palette of the graphic list MgraColor(MilGraContext, (MIL_DOUBLE)PALETTE_COLORS[0]); MgraArcFill(MilGraContext, MilGraList, -BRUSH_RADIUS, -BRUSH_RADIUS, BRUSH_RADIUS, BRUSH_RADIUS, 0, 360); MgraControl(MilGraContext, M_INPUT_UNITS, M_DISPLAY); MgraControlList(MilGraList, M_GRAPHIC_INDEX(0), M_DEFAULT, M_SELECTABLE, M_DISABLE); MgraColor(MilGraContext, M_COLOR_BLACK); MgraRectAngle(MilGraContext, MilGraList, 0, 0, SQUARE_SIZE + 2 * COLOR_SPACING, (NB_COLORS+1) * (SQUARE_SIZE + COLOR_SPACING) + COLOR_SPACING, 0, M_FILLED); MgraControlList(MilGraList, M_GRAPHIC_INDEX(1), M_DEFAULT, M_SELECTABLE, M_DISABLE); for(MIL_INT c = 0; c < NB_COLORS; c++) { MgraColor(MilGraContext, (MIL_DOUBLE)PALETTE_COLORS[c]); MgraRectAngle(MilGraContext, MilGraList, COLOR_SPACING, COLOR_SPACING + c * (SQUARE_SIZE + COLOR_SPACING), SQUARE_SIZE, SQUARE_SIZE, 0, M_FILLED); } // Draw the alpha control. MgraColor(MilGraContext, M_COLOR_WHITE); MgraRectAngle(MilGraContext, MilGraList, COLOR_SPACING, COLOR_SPACING + NB_COLORS * (SQUARE_SIZE + COLOR_SPACING), SQUARE_SIZE/2, SQUARE_SIZE, 0, M_FILLED); MIL_INT MinusLabel = MgraInquireList(MilGraList, M_LIST, M_DEFAULT, M_LAST_LABEL, M_NULL); MgraRectAngle(MilGraContext, MilGraList, COLOR_SPACING + SQUARE_SIZE/2, COLOR_SPACING + NB_COLORS * (SQUARE_SIZE + COLOR_SPACING), SQUARE_SIZE/2, SQUARE_SIZE, 0, M_FILLED); MIL_INT PlusLabel = MgraInquireList(MilGraList, M_LIST, M_DEFAULT, M_LAST_LABEL, M_NULL); MgraControl(MilGraContext, M_TEXT_ALIGN_HORIZONTAL, M_CENTER); MgraControl(MilGraContext, M_TEXT_ALIGN_VERTICAL, M_CENTER); MgraControl(MilGraContext, M_BACKGROUND_MODE, M_TRANSPARENT); MgraControl(MilGraContext, M_SELECTABLE, M_DISABLE); MgraColor(MilGraContext, M_COLOR_BLACK); MgraText(MilGraContext, MilGraList, COLOR_SPACING + SQUARE_SIZE/2, COLOR_SPACING + SQUARE_SIZE/3 + NB_COLORS * (SQUARE_SIZE + COLOR_SPACING), MIL_TEXT("- a +")); DrawAlphaString(MilGraContext, MilGraList, INITIAL_ALPHA_VALUE); // Associate the graphic list to the display. MdispControl(MilDisplay, M_ASSOCIATED_GRAPHIC_LIST_ID, MilGraList); // Fill the hook structure. SHookData HookData; HookData.MilDisplay = MilDisplay; HookData.MilGraContext = MilGraContext; HookData.MilGraList = MilGraList; HookData.DrawingColor = PALETTE_COLORS[0]; HookData.MilDisplayedImage = MilImage; HookData.MilOverlay = MilOverlay; HookData.MilUserOverlay = MilUserOverlay; HookData.OverlayTransparentColor = OverlayTransparentColor; HookData.Alpha = INITIAL_ALPHA_VALUE; HookData.MinusAlphaLabel = MinusLabel; HookData.PlusAlphaLabel = PlusLabel; // Hook a function to the display mouse. MdispHookFunction(MilDisplay, M_MOUSE_MOVE, MouseMove, &HookData); // Hook a function to the click of a graphic object. MgraControlList(MilGraList, M_LIST, M_DEFAULT, M_MULTIPLE_SELECTION, M_DISABLE); MgraHookFunction(MilGraList, M_GRAPHIC_SELECTION_MODIFIED, GraphicSelected, &HookData); // Make the graphic list interactive. MdispControl(MilDisplay, M_GRAPHIC_LIST_INTERACTIVE, M_ENABLE); // Print message. MosPrintf(MIL_TEXT("You can now interact with the display to modify the alpha-blended\n") MIL_TEXT("overlay with your mouse:\n") MIL_TEXT(" - Left click to select a brush color from the palette.\n") MIL_TEXT(" - Left click on the plus or minus to change the alpha value.\n") MIL_TEXT(" - Left click and move the mouse to draw some lines.\n") MIL_TEXT(" - Right click and move the mouse to erase areas.\n\n") MIL_TEXT("Press <Enter> to continue.\n\n")); MosGetch(); // Unhook a function to the click of a graphic object. MgraHookFunction(MilGraList, M_GRAPHIC_SELECTION_MODIFIED + M_UNHOOK, GraphicSelected, &HookData); // Unhook a function to the display mouse. MdispHookFunction(MilDisplay, M_MOUSE_MOVE + M_UNHOOK, MouseMove, &HookData); // Free allocations. MbufFree(MilUserOverlay); MbufFree(MilImage); MgraFree(MilGraList); MgraFree(MilGraContext); MdispFree(MilDisplay); MsysFree(MilSystem); MappFree(MilApplication); return 0; } //***************************************************************************** // AlphaBlend. Blends the displayed image with the user overlay, coying only // non transparent pixels. //***************************************************************************** void AlphaBlend(MIL_ID MilDisplayedImage, MIL_ID MilOverlay, MIL_ID MilUserOverlay, MIL_INT UserTransparentColor, MIL_INT OverlayTransparentColor, MIL_INT Alpha) { if(Alpha > 0) { // Perform the alpha-blending between the overlay image and the image. MimArithMultiple(MilDisplayedImage, 256-Alpha, MilUserOverlay, (MIL_DOUBLE)Alpha, 256, MilOverlay, M_MULTIPLY_ACCUMULATE_2, M_DEFAULT); MbufClearCond(MilOverlay, M_RGB888_R(OverlayTransparentColor), M_RGB888_G(OverlayTransparentColor), M_RGB888_B(OverlayTransparentColor), MilUserOverlay, M_EQUAL, (MIL_DOUBLE)UserTransparentColor); } else MbufClear(MilOverlay, (MIL_DOUBLE)OverlayTransparentColor); } //***************************************************************************** // MouseMove. Display callback that draws an arc each time the mouse is moved // and a button is clicked. //***************************************************************************** MIL_INT MFTYPE MouseMove(MIL_INT HookType, MIL_ID MilEvent, void *pUserData) { SHookData* pHookData = (SHookData*) pUserData; // Get the color to draw the arc. MIL_INT ArcToDrawColor = -1; MIL_INT CombinationKeys; MdispGetHookInfo(MilEvent, M_COMBINATION_KEYS, &CombinationKeys); if((CombinationKeys & M_MOUSE_LEFT_BUTTON) == M_MOUSE_LEFT_BUTTON) ArcToDrawColor = pHookData->DrawingColor; else if((CombinationKeys & M_MOUSE_RIGHT_BUTTON) == M_MOUSE_RIGHT_BUTTON) ArcToDrawColor = USER_TRANSPARENT_COLOR; // Get the position of the mouse in the displayed image. MIL_DOUBLE MousePosBufX; MIL_DOUBLE MousePosBufY; MdispGetHookInfo(MilEvent, M_MOUSE_POSITION_BUFFER_X, &MousePosBufX); MdispGetHookInfo(MilEvent, M_MOUSE_POSITION_BUFFER_Y, &MousePosBufY); if(ArcToDrawColor != -1) { // Draw the arc in the image. MgraColor(pHookData->MilGraContext, (MIL_DOUBLE)ArcToDrawColor); MgraArcFill(pHookData->MilGraContext, pHookData->MilUserOverlay, MousePosBufX, MousePosBufY, BRUSH_RADIUS, BRUSH_RADIUS, 0, 360); // Refresh the overlay. MdispControl(pHookData->MilDisplay, M_UPDATE, M_DISABLE); AlphaBlend(pHookData->MilDisplayedImage, pHookData->MilOverlay, pHookData->MilUserOverlay, USER_TRANSPARENT_COLOR, pHookData->OverlayTransparentColor, pHookData->Alpha); MdispControl(pHookData->MilDisplay, M_UPDATE, M_ENABLE); } // Move the brush. MgraControlList(pHookData->MilGraList, M_GRAPHIC_INDEX(0), M_DEFAULT, M_POSITION_X, MousePosBufX); MgraControlList(pHookData->MilGraList, M_GRAPHIC_INDEX(0), M_DEFAULT, M_POSITION_Y, MousePosBufY); return 0; } //***************************************************************************** // MouseMove. Graphic list callback get the color of the palette of the // selected rectangle. //***************************************************************************** MIL_INT MFTYPE GraphicSelected(MIL_INT HookType, MIL_ID MilEvent, void *pUserData) { SHookData* pHookData = (SHookData*) pUserData; // Get the label of the selected graphic. MIL_INT GraphicSelected; MgraGetHookInfo(MilEvent, M_GRAPHIC_LABEL_VALUE, &GraphicSelected); MIL_ID MilGraList; MgraGetHookInfo(MilEvent, M_GRAPHIC_LIST_ID, &MilGraList); // If a graphic was selected. if(GraphicSelected != M_NO_LABEL) { bool UpdateAlpha = true; if(GraphicSelected == pHookData->MinusAlphaLabel) pHookData->Alpha -= pHookData->Alpha > 4 ? ALPHA_INCREMENT : 0; else if(GraphicSelected == pHookData->PlusAlphaLabel) pHookData->Alpha += pHookData->Alpha < 251 ? ALPHA_INCREMENT : 0; else { // Set the color of the brush. MgraInquireList(MilGraList, M_GRAPHIC_LABEL(GraphicSelected), M_DEFAULT, M_COLOR + M_TYPE_MIL_INT, &pHookData->DrawingColor); MgraControlList(MilGraList, M_GRAPHIC_INDEX(0), M_DEFAULT, M_COLOR, pHookData->DrawingColor); UpdateAlpha = false; } MgraControlList(MilGraList, M_GRAPHIC_LABEL(GraphicSelected), M_DEFAULT, M_GRAPHIC_SELECTED, M_FALSE); // Update the alpha blending. if(UpdateAlpha) { MdispControl(pHookData->MilDisplay, M_UPDATE, M_DISABLE); MIL_INT NbGraphics = MgraInquireList(MilGraList, M_LIST, M_DEFAULT, M_NUMBER_OF_GRAPHICS, M_NULL); MgraControlList(MilGraList, M_GRAPHIC_INDEX(NbGraphics-1), M_DEFAULT, M_DELETE, M_DEFAULT); AlphaBlend(pHookData->MilDisplayedImage, pHookData->MilOverlay, pHookData->MilUserOverlay, USER_TRANSPARENT_COLOR, pHookData->OverlayTransparentColor, pHookData->Alpha); DrawAlphaString(pHookData->MilGraContext, MilGraList, pHookData->Alpha); MdispControl(pHookData->MilDisplay, M_UPDATE, M_ENABLE); } } return 0; } //***************************************************************************** // DrawAlphaString. Draw the string of the alpha value. //***************************************************************************** void DrawAlphaString(MIL_ID MilGraContext, MIL_ID MilGraList, MIL_INT Alpha) { MIL_TEXT_CHAR AlphaString[6]; MosSprintf(AlphaString, 6, MIL_TEXT(" %i "), Alpha); MgraColor(MilGraContext, M_COLOR_BLACK); MgraText(MilGraContext, MilGraList, COLOR_SPACING + SQUARE_SIZE/2, COLOR_SPACING + 2*SQUARE_SIZE/3 + NB_COLORS * (SQUARE_SIZE + COLOR_SPACING), AlphaString); }