max-samplers: use the maximum number of textures in all shader stages

Reviewed-by: Brian Paul <brianp@vmware.com>

v2: added changes from Brian (only require GL 2.0, print the limits)

3 files changed, 283 insertions, 0 deletions

diff --git a/tests/all.tests b/tests/all.tests
index 0f2a1efb0..0f80e0bab 100644
--- a/tests/all.tests
+++ b/tests/all.tests
@@ -672,6 +672,7 @@ add_plain_test(gl20, 'depth-tex-modes-glsl')
 add_plain_test(gl20, 'fragment-and-vertex-texturing')
 gl20['incomplete-texture-glsl'] = concurrent_test('incomplete-texture -auto glsl')
 add_plain_test(gl20, 'tex3d-npot')
+add_concurrent_test(gl20, 'max-samplers')
 
 gl21 = Group()
 spec['!OpenGL 2.1'] = gl21
diff --git a/tests/texturing/CMakeLists.gl.txt b/tests/texturing/CMakeLists.gl.txt
index c9e5d1117..0534c88a2 100644
--- a/tests/texturing/CMakeLists.gl.txt
+++ b/tests/texturing/CMakeLists.gl.txt
@@ -40,6 +40,7 @@ piglit_add_executable (lodclamp-between lodclamp-between.c)
 piglit_add_executable (lodclamp-between-max lodclamp-between-max.c)
 piglit_add_executable (max-texture-size max-texture-size.c)
 piglit_add_executable (max-texture-size-level max-texture-size-level.c)
+piglit_add_executable (max-samplers max-samplers.c)
 piglit_add_executable (mipmap-setup mipmap-setup.c)
 piglit_add_executable (proxy-texture proxy-texture.c)
 piglit_add_executable (rg-draw-pixels rg-draw-pixels.c)
diff --git a/tests/texturing/max-samplers.c b/tests/texturing/max-samplers.c
new file mode 100644
index 000000000..ccef4a193
--- /dev/null
+++ b/tests/texturing/max-samplers.c
@@ -0,0 +1,281 @@
+/*
+ * 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.
+ *
+ * Authors:
+ *  Marek Olšák <maraeo@gmail.com>
+ */
+
+/**
+ * Tests that binding the maximum number of textures in both the vertex and
+ * fragment shader works.
+ */
+
+#include <string.h>
+#include "piglit-util-gl-common.h"
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+	config.supports_gl_compat_version = 20;
+
+	config.window_width = 300;
+	config.window_height = 300;
+	config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DOUBLE;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+static const char *vs_source =
+	"#define NUM %i \n"
+	"uniform sampler2D vertex_tex[NUM]; \n"
+	"uniform int vertex_index;"
+	"varying vec3 vertex_tex_color; \n"
+	"void main() \n"
+	"{ \n"
+	"	int i; \n"
+	"	gl_Position = gl_Vertex; \n"
+	"	vertex_tex_color = vec3(0.0); \n"
+	"	for (i = 0; i < NUM; i++) \n"
+	"		if (i == vertex_index) \n"
+	"			vertex_tex_color = texture2DLod(vertex_tex[i], vec2(0.5), 0.0).xyz; \n"
+	"} \n";
+
+static const char *vs_source_no_textures =
+	"varying vec3 vertex_tex_color; \n"
+	"void main() \n"
+	"{ \n"
+	"	gl_Position = gl_Vertex; \n"
+	"	vertex_tex_color = vec3(0.0); \n"
+	"} \n";
+
+static const char *fs_source =
+	"#define NUM %i \n"
+	"uniform sampler2D fragment_tex[NUM]; \n"
+	"uniform int fragment_index;"
+	"varying vec3 vertex_tex_color; \n"
+	"void main() \n"
+	"{ \n"
+	"	int i; \n"
+	"	vec3 fragment_tex_color = vec3(0.0); \n"
+	"	for (i = 0; i < NUM; i++) \n"
+	"		if (i == fragment_index) \n"
+	"			fragment_tex_color = texture2D(fragment_tex[i], vec2(0.5), 0.0).xyz; \n"
+	"	gl_FragColor = vec4(fragment_tex_color + vertex_tex_color, 1.0); \n"
+	"} \n";
+
+GLuint prog;
+static int max_vs_textures, max_fs_textures;
+
+static void
+get_texture_color(int unit, float out[3])
+{
+	out[0] = (unit % 16) / 15.0;
+	out[1] = (unit / 16) / 15.0;
+	out[2] = 0;
+}
+
+static void
+set_uniform(GLuint prog, const char *name, int value)
+{
+	GLuint loc = glGetUniformLocation(prog, name);
+	if (loc != -1)
+		glUniform1i(loc, value);
+}
+
+static GLvoid
+draw_rect_core(int ix, int iy, int iw, int ih)
+{
+	float x = -1 + 2.0*ix/piglit_width;
+	float y = -1 + 2.0*iy/piglit_height;
+	float w = 2.0*iw/piglit_width;
+	float h = 2.0*ih/piglit_height;
+	float verts[4][4];
+	GLuint vbo;
+
+	verts[0][0] = x;
+	verts[0][1] = y;
+	verts[0][2] = 0.0;
+	verts[0][3] = 1.0;
+	verts[1][0] = x + w;
+	verts[1][1] = y;
+	verts[1][2] = 0.0;
+	verts[1][3] = 1.0;
+	verts[2][0] = x + w;
+	verts[2][1] = y + h;
+	verts[2][2] = 0.0;
+	verts[2][3] = 1.0;
+	verts[3][0] = x;
+	verts[3][1] = y + h;
+	verts[3][2] = 0.0;
+	verts[3][3] = 1.0;
+
+	glGenBuffers(1, &vbo);
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
+
+	glEnableVertexAttribArray(0);
+	glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 0, NULL);
+
+	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+
+	glDisableVertexAttribArray(0);
+	glDeleteBuffers(1, &vbo);
+}
+
+static GLboolean
+probe_pixel(int unit, int x, int y)
+{
+	float expected[3];
+
+	get_texture_color(unit, expected);
+
+	if (piglit_probe_pixel_rgb(x, y, expected))
+		return GL_TRUE;
+
+	printf("  When testing texture unit %i\n", unit);
+	return GL_FALSE;
+}
+
+enum piglit_result
+piglit_display(void)
+{
+	GLboolean pass = GL_TRUE;
+	int i, unit, x, y;
+
+	glClear(GL_COLOR_BUFFER_BIT);
+
+	x = 0;
+	y = 0;
+	unit = 0;
+
+	set_uniform(prog, "fragment_index", max_fs_textures);
+	for (i = 0; i < max_vs_textures; i++) {
+		set_uniform(prog, "vertex_index", i);
+		draw_rect_core(x, y, 20, 20);
+		pass = probe_pixel(unit, x+10, y+10) && pass;
+
+		unit++;
+		x += 20;
+		if (x+20 > piglit_width) {
+			x = 0;
+			y += 20;
+		}
+	}
+
+	set_uniform(prog, "vertex_index", max_vs_textures);
+	for (i = 0; i < max_fs_textures; i++) {
+		set_uniform(prog, "fragment_index", i);
+		draw_rect_core(x, y, 20, 20);
+		pass = probe_pixel(unit, x+10, y+10) && pass;
+
+		unit++;
+		x += 20;
+		if (x+20 > piglit_width) {
+			x = 0;
+			y += 20;
+		}
+	}
+
+	piglit_check_gl_error(GL_NO_ERROR);
+	piglit_present_results();
+
+	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}
+
+static void
+set_texture(int unit)
+{
+	GLuint tex;
+	float color[3];
+
+	get_texture_color(unit, color);
+
+	glGenTextures(1, &tex);
+	glActiveTexture(GL_TEXTURE0 + unit);
+	glBindTexture(GL_TEXTURE_2D, tex);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, 1, 1, 0,
+		     GL_RGB, GL_FLOAT, color);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+	piglit_check_gl_error(GL_NO_ERROR);
+}
+
+void
+piglit_init(int argc, char **argv)
+{
+	GLuint vs, fs, vao;
+	int max_combined_textures, i, unit;
+	char str[2048];
+
+	/* get limits */
+	glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, &max_fs_textures);
+	glGetIntegerv(GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS, &max_vs_textures);
+	glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &max_combined_textures);
+	printf("GL_MAX_TEXTURE_IMAGE_UNITS = %d\n", max_fs_textures);
+	printf("GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS = %d\n", max_vs_textures);
+	printf("GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS = %d\n", max_combined_textures);
+
+	assert(max_fs_textures <= max_combined_textures);
+
+	max_vs_textures = MIN2(max_vs_textures, max_combined_textures - max_fs_textures);
+
+	/* compile shaders */
+	if (max_vs_textures) {
+		sprintf(str, vs_source, max_vs_textures);
+		vs = piglit_compile_shader_text(GL_VERTEX_SHADER, str);
+	}
+	else {
+		vs = piglit_compile_shader_text(GL_VERTEX_SHADER, vs_source_no_textures);
+	}
+
+	sprintf(str, fs_source, max_fs_textures);
+	fs = piglit_compile_shader_text(GL_FRAGMENT_SHADER, str);
+
+	prog = piglit_link_simple_program(vs, fs);
+	glUseProgram(prog);
+
+	piglit_check_gl_error(GL_NO_ERROR);
+
+	/* initialize textures */
+	unit = 0;
+	for (i = 0; i < max_vs_textures; i++) {
+		char name[64];
+		sprintf(name, "vertex_tex[%i]", i);
+		set_uniform(prog, name, unit);
+		set_texture(unit);
+		unit++;
+	}
+
+	for (i = 0; i < max_fs_textures; i++) {
+		char name[64];
+		sprintf(name, "fragment_tex[%i]", i);
+		set_uniform(prog, name, unit);
+		set_texture(unit);
+		unit++;
+	}
+
+	glClearColor(0.0, 0.0, 1.0, 1.0);
+
+	if (piglit_get_gl_version() >= 30) {
+		glGenVertexArrays(1, &vao);
+		glBindVertexArray(vao);
+	}
+
+	piglit_check_gl_error(GL_NO_ERROR);
+}