FEAT: initial implementation of OpenGL widget

Oldes · Oldes · commit 4018c5e37d6e · 2019-03-09T18:17:00.000+01:00
Nothing special yet, just displays hard-coded triangle with random background on redraw.
Minimal example:
```
view make gob! [size: 400x400 widget: 'opengl]
```
diff --git a/src/boot/window.r b/src/boot/window.r
@@ -31,6 +31,7 @@ words: [
 	slider
 	date-time
 	group-box
+	opengl
 
 	;- gui-metric
 	border-fixed
diff --git a/src/os/win32/host-event.c b/src/os/win32/host-event.c
@@ -47,6 +47,12 @@
 #include <zmouse.h>
 #include <math.h>	//for floor()
 
+//OpenGL
+#pragma comment(lib, "opengl32")
+#pragma comment(lib, "glu32")
+#include <gl/gl.h>
+#include <gl/glu.h>
+
 //-- Not currently used:
 //#include <windowsx.h>
 //#include <mmsystem.h>
@@ -495,3 +501,106 @@ static REBINT Check_Modifiers(REBINT flags)
 	}
 	return DefWindowProc(hwnd, msg, wParam, xy);
 }
+
+
+/***********************************************************************
+**
+*/	LRESULT CALLBACK REBOL_OpenGL_Proc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
+/*
+**		An OpenGL message handler.
+**
+***********************************************************************/
+{
+	REBGOB *gob;
+	REBCNT flags = 0;
+	HDC hdc;
+	HGLRC hglrc;
+	PIXELFORMATDESCRIPTOR pfd;
+	PAINTSTRUCT ps;
+	
+
+#ifdef __LLP64__
+	gob = (REBGOB *)GetWindowLongPtr(hwnd, GWLP_USERDATA);
+#else
+	gob = (REBGOB *)GetWindowLong(hwnd, GWL_USERDATA);
+#endif
+
+	//if(msg != WM_PAINT)
+	//	printf("OpenGL_Proc - msg: %0X wParam: %0X lParam: %0X gob: %0Xh\n", msg, wParam, lParam, gob);
+	
+	// Handle message:
+	switch (msg)
+	{
+	case WM_PAINT: 
+		hdc = BeginPaint(hwnd, &ps);
+		//TODO: retrive context from gob's handle
+		//hglrc = wglGetCurrentContext();
+		//wglMakeCurrent(hdc, hglrc);
+			//glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+			glBegin(GL_TRIANGLES);
+			glColor3ub(255, 0, 0);    glVertex2d(-0.75, -0.75);
+			glColor3ub(0, 255, 0);    glVertex2d(0.0, 0.75);
+			glColor3ub(0, 0, 255);    glVertex2d(0.75, -0.75);
+			glEnd();
+			glFlush();
+
+			wglSwapBuffers(hdc);
+		//	wglMakeCurrent(hdc, 0);
+			EndPaint(hwnd, &ps);
+		return FALSE;
+	case WM_ERASEBKGND:
+		// for testing purposes, set random background so far...
+		glClearColor(((float)rand()/(float)(RAND_MAX))*1.0, 0.0, 0.0, 0.0);
+
+		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+		break;
+	case WM_SIZE:
+		glViewport(0, 0, LOWORD(lParam), HIWORD(lParam));
+		break;
+	case WM_CREATE:
+		hdc = GetDC(hwnd);
+		ZeroMemory(&pfd, sizeof(pfd));
+		PIXELFORMATDESCRIPTOR pfd = {
+			sizeof(PIXELFORMATDESCRIPTOR),
+			1,
+			PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER,    // Flags
+			PFD_TYPE_RGBA,        // The kind of framebuffer. RGBA or palette.
+			32,                   // Colordepth of the framebuffer.
+			0, 0, 0, 0, 0, 0,
+			0,
+			0,
+			0,
+			0, 0, 0, 0,
+			24,                   // Number of bits for the depthbuffer
+			8,                    // Number of bits for the stencilbuffer
+			0,                    // Number of Aux buffers in the framebuffer.
+			PFD_MAIN_PLANE,
+			0,
+			0, 0, 0
+		};
+		int pf = ChoosePixelFormat(hdc, &pfd);
+		if (!pf) {
+			RL_Print("Could not find a pixel format.. OpenGL cannot create its context.\n");
+			return FALSE;
+		}
+		SetPixelFormat(hdc, pf, &pfd);
+		hglrc = wglCreateContext(hdc);
+		if (hglrc) {
+			wglMakeCurrent(hdc, hglrc);
+		}
+		else {
+			RL_Print("Failed to create OpenGL context!\n");
+			return FALSE;
+		}
+		RL_Print("OPENGL CONTEXT CREATED!\n");
+		RL_Print("Version %s\n", glGetString(GL_VERSION));
+		return FALSE;
+
+	case WM_DESTROY:
+		hglrc = wglGetCurrentContext();
+		wglDeleteContext(hglrc);
+		return FALSE;
+	}
+
+	return REBOL_Window_Proc(hwnd, msg, wParam, lParam);
+}
diff --git a/src/os/win32/host-window.c b/src/os/win32/host-window.c
@@ -101,6 +101,7 @@ typedef HRESULT(WINAPI * GETDPIFORMONITOR_T)(HMONITOR, MONITOR_DPI_TYPE, UINT*,
 extern HINSTANCE App_Instance;		// Set by winmain function
 extern void Host_Crash(char *reason);
 extern LRESULT CALLBACK REBOL_Window_Proc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
+extern LRESULT CALLBACK REBOL_OpenGL_Proc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
 
 //***** Locals *****//
 
@@ -112,6 +113,7 @@ static struct gob_window *Gob_Windows;
 static REBOOL DPI_Aware = FALSE;
 static REBOOL Custom_Cursor = FALSE;
 static HFONT Default_Font = NULL;
+static REBOOL Windows8_And_Newer = FALSE;
 
 static u32* window_ext_words;
 
@@ -311,7 +313,7 @@ static REBCNT Get_Widget_Text(HWND widget, REBVAL *text);
 
 	wc.hIcon         = LoadIcon(App_Instance, MAKEINTRESOURCE(101));
 	wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
-	wc.hbrBackground = NULL;
+	wc.hbrBackground = (HBRUSH)COLOR_WINDOW;
 	wc.style         = CS_HREDRAW | CS_VREDRAW | CS_DBLCLKS;
 
 	wc.cbClsExtra    = 0;
@@ -328,6 +330,10 @@ static REBCNT Get_Widget_Text(HWND widget, REBVAL *text);
 
 	if (!RegisterClassEx(&wc)) Host_Crash("Cannot register window");
 
+	wc.lpfnWndProc = REBOL_OpenGL_Proc;
+	wc.lpszClassName = TXT("RebOpenGL");
+	if (!RegisterClassEx(&wc)) puts("Failed to register OpenGL class");
+
 	Make_Subclass(Class_Name_Button, TEXT("BUTTON"), NULL, TRUE);
 
 	Registered = TRUE;
@@ -543,7 +549,10 @@ static REBCNT Get_Widget_Text(HWND widget, REBVAL *text);
 	REBOOL changed;
 	compositor = GOB_COMPOSITOR(gob);
 	changed = OS_Resize_Window_Buffer(compositor, gob);
-	if (redraw) OS_Compose_Gob(compositor, gob, gob, FALSE); // what if not actually resized?
+	if (redraw) {
+		OS_Compose_Gob(compositor, gob, gob, FALSE); // what if not actually resized?
+		OS_Blit_Window(compositor);
+	}
 	return changed;
 }
 
@@ -635,7 +644,7 @@ static REBCNT Get_Widget_Text(HWND widget, REBVAL *text);
 	//render and blit the GOB
 	compositor = GOB_COMPOSITOR(wingob);
 	OS_Compose_Gob(compositor, wingob, gob, FALSE);
-	OS_Blit_Window(compositor);
+	//OS_Blit_Window(compositor); //@@ When used, the content overwrites native widgets which are than invisible:/
 }
 
 
@@ -709,6 +718,10 @@ static REBCNT Get_Widget_Text(HWND widget, REBVAL *text);
 		}
 		return 0;
 	}
+	// Is it a native widget?
+	else if (GOBT_WIDGET == GOB_TYPE(gob)) {
+		RedrawWindow((HWND)VAL_HANDLE(GOB_WIDGET_HANDLE(gob)), NULL, NULL, RDW_INVALIDATE | RDW_ERASE);
+	}
 	// Is it a window gob that needs to be closed?
 	else if (!GOB_PARENT(gob) && GET_GOB_FLAG(gob, GOBF_WINDOW)) {
 		OS_Close_Window(gob);
@@ -819,6 +832,10 @@ static REBCNT Get_Widget_Text(HWND widget, REBVAL *text);
 			class = TXT("BUTTON");
 			style |= BS_GROUPBOX;
 			break;
+		case W_WINDOW_OPENGL:
+			class = TXT("RebOpenGL");
+			style |= CS_OWNDC;
+			break;
 		default:
 			//RL_Print("unknown widget name");
 			return NULL;
@@ -1339,18 +1356,32 @@ static REBCNT Get_Widget_Text(HWND widget, REBVAL *text);
 	Cursor = LoadCursor(NULL, IDC_ARROW);
 	Init_DPI_Awareness();
 
+	// Get information about system version
+	// https://docs.microsoft.com/en-us/windows/desktop/api/winnt/ns-winnt-_osversioninfoa
+	OSVERSIONINFO vi;
+	GetVersionEx(&vi);
 
-	INITCOMMONCONTROLSEX InitCtrlEx;
-	InitCtrlEx.dwSize = sizeof(INITCOMMONCONTROLSEX);
-	InitCtrlEx.dwICC = ICC_STANDARD_CLASSES
-					 | ICC_LINK_CLASS
-					 | ICC_UPDOWN_CLASS
-					 | ICC_LISTVIEW_CLASSES
-					 | ICC_PROGRESS_CLASS
-					 | ICC_BAR_CLASSES
-					 | ICC_DATE_CLASSES;
-	if (!InitCommonControlsEx(&InitCtrlEx)) {
-		RL_Print("Could not initialize common controls! (%u)\n", GetLastError());
+	if (
+		vi.dwMajorVersion >= 10 // Windows10 and newer
+		| (vi.dwMajorVersion >= 6 && vi.dwMinorVersion >= 2) //Win8
+	) {
+		Windows8_And_Newer = TRUE;
+	}
+	
+	if (!(vi.dwMajorVersion == 5 && vi.dwMinorVersion < 1)) {
+		// Enable visual styles (not for Win2000)
+		INITCOMMONCONTROLSEX InitCtrlEx;
+		InitCtrlEx.dwSize = sizeof(INITCOMMONCONTROLSEX);
+		InitCtrlEx.dwICC = ICC_STANDARD_CLASSES
+						 | ICC_LINK_CLASS
+						 | ICC_UPDOWN_CLASS
+						 | ICC_LISTVIEW_CLASSES
+						 | ICC_PROGRESS_CLASS
+						 | ICC_BAR_CLASSES
+						 | ICC_DATE_CLASSES;
+		if (!InitCommonControlsEx(&InitCtrlEx)) {
+			RL_Print("Could not initialize common controls!\n");
+		}
 	}
 }
 
