From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Thu, 20 Mar 2014 21:51:48 +0000 (+0100)
Subject: Emulate glReadPixels of GL_ALPHA.
X-Git-Tag: 1.1~12^2~14
X-Git-Url: https://git.sesse.net/?p=movit;a=commitdiff_plain;h=a5f32397f9c23fa8644fe195865d6c36685cf866;hp=5c3f76b097c3f3ef1e454f574068a2434c64fa4a

Emulate glReadPixels of GL_ALPHA.
---

diff --git a/test_util.cpp b/test_util.cpp
index 8f81211..d7e4fed 100644
--- a/test_util.cpp
+++ b/test_util.cpp
@@ -143,12 +143,16 @@ void EffectChainTester::run(float *out_data, GLenum format, Colorspace color_spa
 
 	glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 	check_error();
-	if (!epoxy_is_desktop_gl() && (format == GL_RED || format == GL_BLUE)) {
+	if (!epoxy_is_desktop_gl() && (format == GL_RED || format == GL_BLUE || format == GL_ALPHA)) {
 		// GLES will only read GL_RGBA.
 		float *temp = new float[width * height * 4];
 		glReadPixels(0, 0, width, height, GL_RGBA, GL_FLOAT, temp);
 		check_error();
-		if (format == GL_BLUE) {
+		if (format == GL_ALPHA) {
+			for (int i = 0; i < width * height; ++i) {
+				out_data[i] = temp[i * 4 + 3];
+			}
+		} else if (format == GL_BLUE) {
 			for (int i = 0; i < width * height; ++i) {
 				out_data[i] = temp[i * 4 + 2];
 			}
@@ -180,12 +184,16 @@ void EffectChainTester::run(unsigned char *out_data, GLenum format, Colorspace c
 
 	glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 	check_error();
-	if (!epoxy_is_desktop_gl() && (format == GL_RED || format == GL_BLUE)) {
+	if (!epoxy_is_desktop_gl() && (format == GL_RED || format == GL_BLUE || format == GL_ALPHA)) {
 		// GLES will only read GL_RGBA.
 		unsigned char *temp = new unsigned char[width * height * 4];
 		glReadPixels(0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, temp);
 		check_error();
-		if (format == GL_BLUE) {
+		if (format == GL_ALPHA) {
+			for (int i = 0; i < width * height; ++i) {
+				out_data[i] = temp[i * 4 + 3];
+			}
+		} else if (format == GL_BLUE) {
 			for (int i = 0; i < width * height; ++i) {
 				out_data[i] = temp[i * 4 + 2];
 			}