Emulate glReadPixels of GL_ALPHA.

diff --git a/test_util.cpp b/test_util.cpp
index 8f812117858c12475b364e08f9eed797a96e73fc..d7e4fede1586723a9037792b431f1459989f58ae 100644 (file)
--- 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];
                        }