X-Git-Url: https://git.ralfj.de/gltest.git/blobdiff_plain/a0cb14324fbd2791d62df09e8d10541f280b60ee..ce1b46da645fdcac80fc9c71082bb5cb40166576:/eglbackend.cpp

diff --git a/eglbackend.cpp b/eglbackend.cpp
index cbe724c..0d765e9 100644
--- a/eglbackend.cpp
+++ b/eglbackend.cpp
@@ -17,6 +17,7 @@
  */
 
 #include "eglbackend.h"
+#include "glutil.h"
 
 #include <stdlib.h>
 #include <stdio.h>
@@ -53,13 +54,7 @@ static void exitEglError(const char *what)
 	exit(1);
 }
 
-static const EGLint context_attribs[] = {
-#ifdef CON_GLES2
-	EGL_CONTEXT_CLIENT_VERSION, 2,
-#endif
-	EGL_NONE
-};
-static const EGLint config_attribs[] = {
+static const EGLint configAttribs[] = {
 	EGL_RED_SIZE,             4,
 	EGL_GREEN_SIZE,           4,
 	EGL_BLUE_SIZE,            4,
@@ -70,6 +65,12 @@ static const EGLint config_attribs[] = {
 #endif
 	EGL_NONE,
 };
+static const EGLint contextAttribs[] = {
+#ifdef CON_GLES2
+	EGL_CONTEXT_CLIENT_VERSION, 2,
+#endif
+	EGL_NONE
+};
 
 VisualID EGLBackend::initialize(Display *xDisplay)
 {
@@ -83,6 +84,7 @@ VisualID EGLBackend::initialize(Display *xDisplay)
 			exitEglError("Failed to initialize EGL");
 		printf("Using EGL version: %d.%d\n", eglMajor, eglMinor);
 		if (eglMajor == 1 && eglMinor < 3) {
+			// Choosing the GL context version requires EGL 1.3
 			fprintf(stderr, "Need at least EGL 1.3 to function properly\n");
 			exit(1);
 		}
@@ -95,11 +97,11 @@ VisualID EGLBackend::initialize(Display *xDisplay)
 		// get an appropriate config
 		EGLConfig configs[1];
 		EGLint count;
-		if (eglChooseConfig(display, config_attribs, configs, 1, &count) == EGL_FALSE){
-			exitEglError("Failed to choose config");
+		if (eglChooseConfig(display, configAttribs, configs, 1, &count) == EGL_FALSE){
+			exitEglError("Failed to choose framebuffer configuration");
 		}
 		if (count == 0) {
-			fprintf(stderr, "Found no matching EGL configuration\n");
+			fprintf(stderr, "Found no matching framebuffer configuration\n");
 			exit(1);
 		}
 		config = configs[0];
@@ -115,11 +117,14 @@ void EGLBackend::createContext(Window window)
 	assert(display != EGL_NO_DISPLAY && context == EGL_NO_CONTEXT);
 	surface = eglCreateWindowSurface(display, config, window, NULL);
 	// create an EGL context and use it with the surface
-	context = eglCreateContext(display, config, EGL_NO_CONTEXT, context_attribs);
+	context = eglCreateContext(display, config, EGL_NO_CONTEXT, contextAttribs);
 	if (context == EGL_NO_CONTEXT)
 		exitEglError("Failed to create context");
 	if (eglMakeCurrent(display, surface, surface, context) == EGL_FALSE)
 		exitEglError("Failed to make context current");
+	printf("Using GL version: %s\n", glGetString(GL_VERSION));
+	// initialise GL utilities
+	resolveFunctionPointers(eglGetProcAddress);
 }
 
 EGLBackend::~EGLBackend()
@@ -146,12 +151,11 @@ void EGLBackend::setSwapInterval(int i) const
 {
 	assert(context != EGL_NO_CONTEXT);
 	// check if swap interval value is supported
-	EGLint val;
-	eglGetConfigAttrib(display, config, EGL_MIN_SWAP_INTERVAL, &val);
-	if (i < val) {
-		fprintf(stderr, "Cannot set swap interval to %d, minimum supported value is %d\n", i, val);
+	if (i < 0) {
+		fprintf(stderr, "Cannot set swap interval to %d, must not be negative\n", i);
 		exit(1);
 	}
+	EGLint val;
 	eglGetConfigAttrib(display, config, EGL_MAX_SWAP_INTERVAL, &val);
 	if (i > val) {
 		fprintf(stderr, "Cannot set swap interval to %d, maximum supported value is %d\n", i, val);