bool movit_srgb_textures_supported;
int movit_num_wrongly_rounded;
bool movit_shader_rounding_supported;
+MovitShaderModel movit_shader_model;
// The rules for objects with nontrivial constructors in static scope
// are somewhat convoluted, and easy to mess up. We simply have a
check_error();
glBindTexture(GL_TEXTURE_2D, dst_texnum);
check_error();
- glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F_ARB, width, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+ glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F, width, 1, 0, GL_RGBA, GL_FLOAT, NULL);
check_error();
glGenFramebuffers(1, &fbo);
glViewport(0, 0, width, 1);
GLuint glsl_program_num = resource_pool.compile_glsl_program(
- read_file("vs.vert"), read_file("texture1d.frag"));
+ read_version_dependent_file("vs", "vert"),
+ read_version_dependent_file("texture1d", "frag"));
glUseProgram(glsl_program_num);
check_error();
glUniform1i(glGetUniformLocation(glsl_program_num, "tex"), 0); // Bind the 2D sampler.
// Now read the data back and see what the card did.
// (We only look at the red channel; the others will surely be the same.)
// We assume a linear ramp; anything else will give sort of odd results here.
- float out_data[width];
- glReadPixels(0, 0, width, 1, GL_RED, GL_FLOAT, out_data);
+ float out_data[width * 4];
+ glReadPixels(0, 0, width, 1, GL_RGBA, GL_FLOAT, out_data);
check_error();
float biggest_jump = 0.0f;
for (unsigned i = 1; i < width; ++i) {
- assert(out_data[i] >= out_data[i - 1]);
- biggest_jump = max(biggest_jump, out_data[i] - out_data[i - 1]);
+ assert(out_data[i * 4] >= out_data[(i - 1) * 4]);
+ biggest_jump = max(biggest_jump, out_data[i * 4] - out_data[(i - 1) * 4]);
}
assert(biggest_jump > 0.0);
glViewport(0, 0, 512, 1);
GLuint glsl_program_num = resource_pool.compile_glsl_program(
- read_file("vs.vert"), read_file("texture1d.frag"));
+ read_version_dependent_file("vs", "vert"),
+ read_version_dependent_file("texture1d", "frag"));
glUseProgram(glsl_program_num);
check_error();
glUniform1i(glGetUniformLocation(glsl_program_num, "tex"), 0); // Bind the 2D sampler.
// Now read the data back and see what the card did. (Ignore the last value.)
// (We only look at the red channel; the others will surely be the same.)
- unsigned char out_data[512];
- glReadPixels(0, 0, 512, 1, GL_RED, GL_UNSIGNED_BYTE, out_data);
+ unsigned char out_data[512 * 4];
+ glReadPixels(0, 0, 512, 1, GL_RGBA, GL_UNSIGNED_BYTE, out_data);
check_error();
int wrongly_rounded = 0;
for (unsigned i = 0; i < 255; ++i) {
- if (out_data[i * 2 + 0] != i) {
+ if (out_data[(i * 2 + 0) * 4] != i) {
++wrongly_rounded;
}
- if (out_data[i * 2 + 1] != i + 1) {
+ if (out_data[(i * 2 + 1) * 4] != i + 1) {
++wrongly_rounded;
}
}
bool check_extensions()
{
+ // GLES generally doesn't use extensions as actively as desktop OpenGL.
+ // For now, we say that for GLES, we require GLES 3, which has everything
+ // we need.
+ //
+ // Since we use implicit #version 100, we don't have round(). We will
+ // fix this at some later stage.
+ if (!epoxy_is_desktop_gl()) {
+ if (epoxy_gl_version() >= 30) {
+ movit_srgb_textures_supported = true;
+ movit_shader_rounding_supported = false;
+ } else {
+ return false;
+ }
+ }
+
// We fundamentally need FBOs and floating-point textures.
// FBOs are covered by OpenGL 1.5, and are not an extension there.
// Floating-point textures are part of OpenGL 3.0 and newer.
return true;
}
+double get_glsl_version()
+{
+ char *glsl_version_str = strdup((const char *)glGetString(GL_SHADING_LANGUAGE_VERSION));
+
+ // Skip past the first period.
+ char *ptr = strchr(glsl_version_str, '.');
+ assert(ptr != NULL);
+ ++ptr;
+
+ // Now cut the string off at the next period or space, whatever comes first
+ // (unless the string ends first).
+ while (*ptr && *ptr != '.' && *ptr != ' ') {
+ ++ptr;
+ }
+ *ptr = '\0';
+
+ // Now we have something on the form X.YY. We convert it to a float, and hope
+ // that if it's inexact (e.g. 1.30), atof() will round the same way the
+ // compiler will.
+ float glsl_version = atof(glsl_version_str);
+ free(glsl_version_str);
+
+ return glsl_version;
+}
+
} // namespace
bool init_movit(const string& data_directory, MovitDebugLevel debug_level)
if (!check_extensions()) {
return false;
}
+
+ // Find out what shader model we should compile for.
+ if (epoxy_is_desktop_gl()) {
+ if (get_glsl_version() >= 1.30) {
+ movit_shader_model = MOVIT_GLSL_130;
+ } else {
+ movit_shader_model = MOVIT_GLSL_110;
+ }
+ } else {
+ movit_shader_model = MOVIT_ESSL_300;
+ }
+
measure_texel_subpixel_precision();
measure_roundoff_problems();