LibGL: Implement `glGetTexLevelParameteriv`

Userland/Libraries/LibGL/GL/gl.h

@@ -580,6 +580,7 @@ GLAPI void glBitmap(GLsizei width, GLsizei height, GLfloat xorig, GLfloat yorig,
 GLAPI void glCopyTexImage2D(GLenum target, GLint level, GLenum internalformat, GLint x, GLint y, GLsizei width, GLsizei height, GLint border);
 GLAPI void glRectf(GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2);
 GLAPI void glRecti(GLint x1, GLint y1, GLint x2, GLint y2);
+GLAPI void glGetTexLevelParameteriv(GLenum target, GLint level, GLenum pname, GLint* params);
 
 #ifdef __cplusplus
 }

Userland/Libraries/LibGL/GLContext.h

@@ -116,6 +116,7 @@ public:
     virtual void gl_light_model(GLenum pname, GLfloat x, GLfloat y, GLfloat z, GLfloat w) = 0;
     virtual void gl_bitmap(GLsizei width, GLsizei height, GLfloat xorig, GLfloat yorig, GLfloat xmove, GLfloat ymove, GLubyte const* bitmap) = 0;
     virtual void gl_copy_tex_image_2d(GLenum target, GLint level, GLenum internalformat, GLint x, GLint y, GLsizei width, GLsizei height, GLint border) = 0;
+    virtual void gl_get_tex_parameter_integerv(GLenum target, GLint level, GLenum pname, GLint* params) = 0;
     virtual void gl_rect(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2) = 0;
 
     virtual void present() = 0;

Userland/Libraries/LibGL/GLTexture.cpp

@@ -61,3 +61,8 @@ void glCopyTexImage2D(GLenum target, GLint level, GLenum internalformat, GLint x
 {
     g_gl_context->gl_copy_tex_image_2d(target, level, internalformat, x, y, width, height, border);
 }
+
+void glGetTexLevelParameteriv(GLenum target, GLint level, GLenum pname, GLint* params)
+{
+    g_gl_context->gl_get_tex_parameter_integerv(target, level, pname, params);
+}

Userland/Libraries/LibGL/SoftwareGLContext.cpp

@@ -2658,6 +2658,27 @@ void SoftwareGLContext::gl_copy_tex_image_2d(GLenum target, GLint level, GLenum
         target, level, internalformat, x, y, width, height, border);
 }
 
+void SoftwareGLContext::gl_get_tex_parameter_integerv(GLenum target, GLint level, GLenum pname, GLint* params)
+{
+    RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
+    // FIXME: support targets other than GL_TEXTURE_2D
+    RETURN_WITH_ERROR_IF(target != GL_TEXTURE_2D, GL_INVALID_ENUM);
+    // FIXME: support other parameter names
+    RETURN_WITH_ERROR_IF(pname < GL_TEXTURE_WIDTH || pname > GL_TEXTURE_HEIGHT, GL_INVALID_ENUM);
+    RETURN_WITH_ERROR_IF(level < 0 || level > Texture2D::LOG2_MAX_TEXTURE_SIZE, GL_INVALID_VALUE);
+    // FIXME: GL_INVALID_VALUE is generated if target is GL_TEXTURE_BUFFER and level is not zero
+    // FIXME: GL_INVALID_OPERATION is generated if GL_TEXTURE_COMPRESSED_IMAGE_SIZE is queried on texture images with an uncompressed internal format or on proxy targets
+
+    switch (pname) {
+    case GL_TEXTURE_HEIGHT:
+        *params = m_active_texture_unit->bound_texture_2d()->height_at_lod(level);
+        break;
+    case GL_TEXTURE_WIDTH:
+        *params = m_active_texture_unit->bound_texture_2d()->width_at_lod(level);
+        break;
+    }
+}
+
 void SoftwareGLContext::gl_rect(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2)
 {
     APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_rect, x1, y1, x2, y2);

Userland/Libraries/LibGL/SoftwareGLContext.h

@@ -129,6 +129,7 @@ public:
     virtual void gl_light_model(GLenum pname, GLfloat x, GLfloat y, GLfloat z, GLfloat w) override;
     virtual void gl_bitmap(GLsizei width, GLsizei height, GLfloat xorig, GLfloat yorig, GLfloat xmove, GLfloat ymove, GLubyte const* bitmap) override;
     virtual void gl_copy_tex_image_2d(GLenum target, GLint level, GLenum internalformat, GLint x, GLint y, GLsizei width, GLsizei height, GLint border) override;
+    virtual void gl_get_tex_parameter_integerv(GLenum target, GLint level, GLenum pname, GLint* params) override;
     virtual void gl_rect(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2) override;
 
     virtual void present() override;