Merge branch 'opengl-screenshot-fix' into 'master'

Fix for screenshots taken in OpenGL with resolution 1366x768

Fix for this bug: https://mb.srb2.org/showthread.php?t=39882 (also reported here: https://mb.srb2.org/showthread.php?p=793077#10)

This is basically porting GZDoom's own fix for the same issue (I stumbled on a Zandronum thread about the same issue from google images, and one user mentioned GZDoom had fixed it): d31a0b77fd

See merge request !192

src/hardware/r_opengl/r_opengl.c

@@ -244,6 +244,7 @@ FUNCPRINTF void DBG_Printf(const char *lpFmt, ...)
 #define pglMaterialfv glMaterialfv
 
 /* Raster functions */
+#define pglPixelStorei glPixelStorei
 #define pglReadPixels glReadPixels
 
 /* Texture mapping */
@@ -262,15 +263,8 @@ FUNCPRINTF void DBG_Printf(const char *lpFmt, ...)
 /* texture mapping */ //GL_EXT_copy_texture
 #ifndef KOS_GL_COMPATIBILITY
 #define pglCopyTexImage2D glCopyTexImage2D
+#endif
 
-/* GLU functions */
-#define pgluBuild2DMipmaps gluBuild2DMipmaps
-#endif
-#ifndef MINI_GL_COMPATIBILITY
-/* 1.3 functions for multitexturing */
-#define pglActiveTexture glActiveTexture
-#define pglMultiTexCoord2f glMultiTexCoord2f
-#endif
 #else //!STATIC_OPENGL
 
 /* 1.0 functions */
@@ -365,6 +359,8 @@ typedef void (APIENTRY * PFNglMaterialfv) (GLint face, GLenum pname, GLfloat *pa
 static PFNglMaterialfv pglMaterialfv;
 
 /* Raster functions */
+typedef void (APIENTRY * PFNglPixelStorei) (GLenum pname, GLint param);
+static PFNglPixelStorei pglPixelStorei;
 typedef void (APIENTRY  * PFNglReadPixels) (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLvoid *pixels);
 static PFNglReadPixels pglReadPixels;
 
@@ -391,7 +387,7 @@ static PFNglBindTexture pglBindTexture;
 /* texture mapping */ //GL_EXT_copy_texture
 typedef void (APIENTRY * PFNglCopyTexImage2D) (GLenum target, GLint level, GLenum internalformat, GLint x, GLint y, GLsizei width, GLsizei height, GLint border);
 static PFNglCopyTexImage2D pglCopyTexImage2D;
-
+#endif
 /* GLU functions */
 typedef GLint (APIENTRY * PFNgluBuild2DMipmaps) (GLenum target, GLint internalFormat, GLsizei width, GLsizei height, GLenum format, GLenum type, const void *data);
 static PFNgluBuild2DMipmaps pgluBuild2DMipmaps;
@@ -403,7 +399,6 @@ static PFNglActiveTexture pglActiveTexture;
 typedef void (APIENTRY *PFNglMultiTexCoord2f) (GLenum, GLfloat, GLfloat);
 static PFNglMultiTexCoord2f pglMultiTexCoord2f;
 #endif
-#endif
 
 #ifndef MINI_GL_COMPATIBILITY
 /* 1.2 Parms */
@@ -494,6 +489,7 @@ boolean SetupGLfunc(void)
 	GETOPENGLFUNC(pglLightModelfv , glLightModelfv)
 	GETOPENGLFUNC(pglMaterialfv , glMaterialfv)
 
+	GETOPENGLFUNC(pglPixelStorei , glPixelStorei)
 	GETOPENGLFUNC(pglReadPixels , glReadPixels)
 
 	GETOPENGLFUNC(pglTexEnvi , glTexEnvi)
@@ -519,35 +515,23 @@ boolean SetupGLfunc(void)
 // This has to be done after the context is created so the version number can be obtained
 boolean SetupGLFunc13(void)
 {
+#ifdef MINI_GL_COMPATIBILITY
+	return false;
+#else
 	const GLubyte *version = pglGetString(GL_VERSION);
 	int glmajor, glminor;
 
 	gl13 = false;
-#ifdef MINI_GL_COMPATIBILITY
-	return false;
-#else
-#ifdef STATIC_OPENGL
-	gl13 = true;
-#else
-
 	// Parse the GL version
 	if (version != NULL)
 	{
 		if (sscanf((const char*)version, "%d.%d", &glmajor, &glminor) == 2)
 		{
 			// Look, we gotta prepare for the inevitable arrival of GL 2.0 code...
-			switch (glmajor)
+			if (glmajor == 1 && glminor >= 3)
-			{
+				gl13 = true;
-				case 1:
+			else if (glmajor > 1)
-					if (glminor == 3) gl13 = true;
+				gl13 = true;
-					break;
-				case 2:
-				case 3:
-				case 4:
-					gl13 = true;
-				default:
-					break;
-			}
 		}
 	}
 
@@ -568,9 +552,6 @@ boolean SetupGLFunc13(void)
 	}
 	else
 		DBG_Printf("GL_ARB_multitexture support: disabled\n");
-#undef GETOPENGLFUNC
-
-#endif
 	return true;
 #endif
 }
@@ -897,7 +878,9 @@ EXPORT void HWRAPI(ReadRect) (INT32 x, INT32 y, INT32 width, INT32 height,
 		GLubyte*top = (GLvoid*)dst_data, *bottom = top + dst_stride * (height - 1);
 		GLubyte *row = malloc(dst_stride);
 		if (!row) return;
+		pglPixelStorei(GL_PACK_ALIGNMENT, 1);
 		pglReadPixels(x, y, width, height, GL_RGB, GL_UNSIGNED_BYTE, dst_data);
+		pglPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 		for(i = 0; i < height/2; i++)
 		{
 			memcpy(row, top, dst_stride);
@@ -913,7 +896,9 @@ EXPORT void HWRAPI(ReadRect) (INT32 x, INT32 y, INT32 width, INT32 height,
 		INT32 j;
 		GLubyte *image = malloc(width*height*3*sizeof (*image));
 		if (!image) return;
+		pglPixelStorei(GL_PACK_ALIGNMENT, 1);
 		pglReadPixels(x, y, width, height, GL_RGB, GL_UNSIGNED_BYTE, image);
+		pglPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 		for (i = height-1; i >= 0; i--)
 		{
 			for (j = 0; j < width; j++)
@@ -1815,13 +1800,11 @@ EXPORT void HWRAPI(SetSpecialState) (hwdspecialstate_t IdState, INT32 Value)
 					min_filter = GL_NEAREST;
 #endif
 			}
-#ifndef STATIC_OPENGL
 			if (!pgluBuild2DMipmaps)
 			{
 				MipMap = GL_FALSE;
 				min_filter = GL_LINEAR;
 			}
-#endif
 			Flush(); //??? if we want to change filter mode by texture, remove this
 			break;
 

src/sdl/ogl_sdl.c

@@ -71,7 +71,6 @@ INT32 oglflags = 0;
 void *GLUhandle = NULL;
 SDL_GLContext sdlglcontext = 0;
 
-#ifndef STATIC_OPENGL
 void *GetGLFunc(const char *proc)
 {
 	if (strncmp(proc, "glu", 3) == 0)
@@ -83,7 +82,6 @@ void *GetGLFunc(const char *proc)
 	}
 	return SDL_GL_GetProcAddress(proc);
 }
-#endif
 
 boolean LoadGL(void)
 {