Add test to verify scaled blitting of {texture, renderbuffer} attachm…

…ents produce same output

This test verifies that same output is produced by scaled blitting
of texture or renderbuffer color attachments with GL_LINEAR filter.
It compares the output from following rendering scenarios:
1. Scaled blit using a single-sampled framebuffer with texture
attachment.
2. Scaled blit using a single-sampled framebuffer with renderbuffer
attachment.

V2: Move the test to spec/arb_framebuffer_object directory.

Signed-off-by: Anuj Phogat <anuj.phogat@gmail.com>
Acked-by: Paul Berry <stereotype441@gmail.com>

tests/all.tests

@@ -1116,6 +1116,7 @@ for format in ('rgba', 'depth', 'stencil'):
 add_plain_test(arb_framebuffer_object, 'fbo-alpha')
 add_plain_test(arb_framebuffer_object, 'fbo-blit-stretch')
 add_plain_test(arb_framebuffer_object, 'fbo-blit-scaled-linear')
+add_plain_test(arb_framebuffer_object, 'fbo-attachments-blit-scaled-linear')
 add_plain_test(arb_framebuffer_object, 'fbo-deriv')
 add_plain_test(arb_framebuffer_object, 'fbo-luminance-alpha')
 add_plain_test(arb_framebuffer_object, 'fbo-getframebufferattachmentparameter-01')

tests/spec/arb_framebuffer_object/CMakeLists.gl.txt

@@ -16,5 +16,6 @@ piglit_add_executable(arb_framebuffer_object-negative-readpixels-no-rb negative-
 piglit_add_executable(same-attachment-glFramebufferTexture2D-GL_DEPTH_STENCIL_ATTACHMENT same-attachment-glFramebufferTexture2D-GL_DEPTH_STENCIL_ATTACHMENT.c)
 piglit_add_executable(same-attachment-glFramebufferRenderbuffer-GL_DEPTH_STENCIL_ATTACHMENT same-attachment-glFramebufferRenderbuffer-GL_DEPTH_STENCIL_ATTACHMENT.c)
 piglit_add_executable (fbo-blit-scaled-linear blit-scaled-linear.cpp)
+piglit_add_executable (fbo-attachments-blit-scaled-linear attachments-blit-scaled-linear.cpp)
 
 # vim: ft=cmake:

tests/spec/arb_framebuffer_object/attachments-blit-scaled-linear.cpp

@@ -0,0 +1,159 @@
+/*
+ * Copyright © 2013 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+/** \file attachments-blit-scaled-linear.cpp
+ *
+ * This test verifies that same output is produced by scaled blitting
+ * of texture or renderbuffer color attachments with GL_LINEAR filter.
+ * It compares the output from following rendering scenarios:
+ * 1. Scaled blit using a single-sampled framebuffer with texture attachment.
+ * 2. Scaled blit using a single-sampled framebuffer with renderbuffer
+ *    attachment.
+ */
+
+#include "piglit-test-pattern.h"
+#include "piglit-fbo.h"
+using namespace piglit_util_fbo;
+using namespace piglit_util_test_pattern;
+
+const int pattern_width = 258; const int pattern_height = 258;
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+	config.supports_gl_compat_version = 10;
+
+	config.window_width = pattern_width * 2;
+	config.window_height = pattern_height;
+	config.window_visual = PIGLIT_GL_VISUAL_DOUBLE | PIGLIT_GL_VISUAL_RGBA;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+static TestPattern *test_pattern;
+const int srcX0 = 6, srcY0 = 7, dstX0 = 0, dstY0 = 0;
+const int srcX1 = pattern_width / 2, srcY1 = pattern_height / 2;
+static Fbo fbo_tex, fbo_rb;
+
+void
+piglit_init(int argc, char **argv)
+{
+	piglit_require_gl_version(21);
+	/* Create two singlesample FBOs with same format and dimensions but
+	 * different color attachment types.
+	 */
+	FboConfig Config(0, pattern_width, pattern_height);
+	Config.attach_texture = true;
+	fbo_tex.setup(Config);
+	Config.attach_texture = false;
+	fbo_rb.setup(Config);
+
+	test_pattern = new Triangles();
+	test_pattern->compile();
+
+	if (!piglit_check_gl_error(GL_NO_ERROR)) {
+		piglit_report_result(PIGLIT_FAIL);
+	}
+}
+
+bool test_blit_scaled_linear()
+{
+	GLfloat scale;
+	GLint samples;
+	bool pass = true, result = true;
+
+	/* Draw the test pattern into the framebuffer with texture
+	 * attachment.
+	 */
+	glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo_tex.handle);
+	glViewport(0, 0, srcX1, srcY1);
+	glGetIntegerv(GL_SAMPLES, &samples);
+	glClear(GL_COLOR_BUFFER_BIT);
+	test_pattern->draw(TestPattern::no_projection);
+
+	/* Blit the framebuffer with texture attachment into the
+	 * framebuffer with renderbuffer attachment without scaling.
+	 */
+	glBindFramebuffer(GL_READ_FRAMEBUFFER, fbo_tex.handle);
+	glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo_rb.handle);
+	glClear(GL_COLOR_BUFFER_BIT);
+	glBlitFramebuffer(0, 0,
+			  fbo_tex.config.width,
+			  fbo_tex.config.height,
+			  0, 0,
+			  fbo_tex.config.width,
+			  fbo_tex.config.height,
+			  GL_COLOR_BUFFER_BIT, GL_NEAREST);
+
+	for(scale = 0.1; scale < 2.5f; scale += 0.1) {
+		glBindFramebuffer(GL_DRAW_FRAMEBUFFER, piglit_winsys_fbo);
+		glClear(GL_COLOR_BUFFER_BIT);
+
+		/* Do scaled blit of fbo_tex to left half of piglit_winsys_fbo.
+                 */
+		glBindFramebuffer(GL_READ_FRAMEBUFFER, fbo_tex.handle);
+		glBindFramebuffer(GL_DRAW_FRAMEBUFFER, piglit_winsys_fbo);
+                glClearColor(0.0, 1.0, 0.0, 1.0);
+		glClear(GL_COLOR_BUFFER_BIT);
+                glClearColor(0.0, 0.0, 0.0, 0.0);
+		glEnable(GL_SCISSOR_TEST);
+		glScissor(0, 0, pattern_width, pattern_height);
+		glBlitFramebuffer(srcX0, srcY0,
+				  srcX1, srcY1,
+				  dstX0, dstY0,
+				  dstX0 + srcX1 * scale, dstY0 + srcY1 * scale,
+				  GL_COLOR_BUFFER_BIT,
+				  GL_LINEAR);
+		glDisable(GL_SCISSOR_TEST);
+
+		/* Do scaled blit of fbo_rb to right half piglit_winsys_fbo. */
+		glBindFramebuffer(GL_READ_FRAMEBUFFER, fbo_rb.handle);
+		glBlitFramebuffer(srcX0, srcY0,
+				  srcX1, srcY1,
+				  pattern_width + dstX0, dstY0,
+				  pattern_width + dstX0 + srcX1 * scale,
+				  dstY0 + srcY1 * scale,
+				  GL_COLOR_BUFFER_BIT,
+				  GL_LINEAR);
+
+		pass = piglit_check_gl_error(GL_NO_ERROR) && pass;
+		glBindFramebuffer(GL_READ_FRAMEBUFFER, piglit_winsys_fbo);
+		result = piglit_probe_rect_halves_equal_rgba(0, 0,
+                                                           piglit_width,
+                                                           piglit_height);
+		pass = result && pass;
+		piglit_present_results();
+		printf("scale = %f, result = %s\n",
+		       scale, result ? "pass" : "fail");
+	}
+	return pass;
+}
+
+enum piglit_result
+piglit_display()
+{
+	bool pass = true;
+	printf("Left Image: Linear scaled blit using texture attachment.\n"
+	       "Right Image: Linear scaled blit using renderbuffer attachment.\n");
+	pass = test_blit_scaled_linear()
+	       && pass;
+	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}