From 3227d8393d857f8df221e5df9383ca203ad418f8 Mon Sep 17 00:00:00 2001 From: David Thompson Date: Thu, 19 Jan 2017 09:24:19 -0500 Subject: render: Add viewports. --- Makefile.am | 1 + chickadee.scm | 18 ++++--- chickadee/render.scm | 13 +++++- chickadee/render/viewport.scm | 106 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 131 insertions(+), 7 deletions(-) create mode 100644 chickadee/render/viewport.scm diff --git a/Makefile.am b/Makefile.am index 7838b0b..fa84dd6 100644 --- a/Makefile.am +++ b/Makefile.am @@ -53,6 +53,7 @@ SOURCES = \ chickadee/render/texture.scm \ chickadee/render/shader.scm \ chickadee/render/vertex-buffer.scm \ + chickadee/render/viewport.scm \ chickadee/render/shapes.scm \ chickadee/render/sprite.scm \ chickadee/render.scm \ diff --git a/chickadee.scm b/chickadee.scm index b9996e1..41a3d90 100644 --- a/chickadee.scm +++ b/chickadee.scm @@ -20,9 +20,12 @@ #:use-module (sdl2) #:use-module (sdl2 events) #:use-module (sdl2 input text) + #:use-module (chickadee color) #:use-module (chickadee window) + #:use-module (chickadee render) #:use-module (chickadee render gl) #:use-module (chickadee render gpu) + #:use-module (chickadee render viewport) #:export (load-hook update-hook before-draw-hook @@ -142,7 +145,13 @@ (controller-axis-event-axis event) (/ (controller-axis-event-value event) 32768.0))))) (with-window window - (let ((update-interval (round (/ 1000 update-hz)))) + (let ((update-interval (round (/ 1000 update-hz))) + (default-viewport + (make-viewport 0 0 window-width window-height + ;; Just a fun color from the Dawnbringer + ;; 32-color palette instead of boring old + ;; black. + #:clear-color (rgb #x45283c)))) (call-with-prompt game-loop-prompt-tag (lambda () ;; Catch SIGINT and kill the loop. @@ -170,11 +179,8 @@ (begin ;; Render a frame. (run-hook before-draw-hook) - (gl-clear-color 0.267 0.141 0.204 1.0) - (gl-clear (logior (attrib-mask color-buffer) - (attrib-mask depth-buffer) - (attrib-mask stencil-buffer))) - (run-hook draw-hook (/ lag update-interval)) + (with-viewport default-viewport + (run-hook draw-hook (/ lag update-interval))) (swap-buffers window) (run-hook after-draw-hook) (loop current-time lag))))))) diff --git a/chickadee/render.scm b/chickadee/render.scm index d55c76e..efb5004 100644 --- a/chickadee/render.scm +++ b/chickadee/render.scm @@ -29,10 +29,13 @@ #:use-module (chickadee render shader) #:use-module (chickadee render texture) #:use-module (chickadee render vertex-buffer) - #:export (current-blend-mode + #:use-module (chickadee render viewport) + #:export (current-viewport + current-blend-mode current-depth-test current-texture current-projection + with-viewport with-blend-mode with-depth-test with-texture @@ -40,11 +43,15 @@ gpu-apply gpu-apply*)) +(define *current-viewport* null-viewport) (define *current-blend-mode* 'replace) (define *current-depth-test* #f) (define *current-texture* null-texture) (define *current-projection* (make-identity-matrix4)) +(define (current-viewport) + *current-viewport*) + (define (current-blend-mode) *current-blend-mode*) @@ -64,6 +71,9 @@ (lambda () body ...) (lambda () (set! name prev))))) +(define-syntax-rule (with-viewport viewport body ...) + (with (*current-viewport* viewport) body ...)) + (define-syntax-rule (with-blend-mode blend-mode body ...) (with (*current-blend-mode* blend-mode) body ...)) @@ -123,6 +133,7 @@ (define-syntax-rule (gpu-apply* shader vertex-array count . uniforms) (begin + (gpu-state-set! *viewport-state* (current-viewport)) (gpu-state-set! *blend-mode-state* (current-blend-mode)) (gpu-state-set! *depth-test-state* (current-depth-test)) (gpu-state-set! *texture-state* (current-texture)) diff --git a/chickadee/render/viewport.scm b/chickadee/render/viewport.scm new file mode 100644 index 0000000..5768406 --- /dev/null +++ b/chickadee/render/viewport.scm @@ -0,0 +1,106 @@ +;;; Chickadee Game Toolkit +;;; Copyright © 2017 David Thompson +;;; +;;; Chickadee is free software: you can redistribute it and/or modify +;;; it under the terms of the GNU General Public License as published +;;; by the Free Software Foundation, either version 3 of the License, +;;; or (at your option) any later version. +;;; +;;; Chickadee is distributed in the hope that it will be useful, but +;;; WITHOUT ANY WARRANTY; without even the implied warranty of +;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +;;; General Public License for more details. +;;; +;;; You should have received a copy of the GNU General Public License +;;; along with this program. If not, see +;;; . + +;;; Commentary: +;; +;; Viewports specify the renderable section of a window. +;; +;;; Code: + +(define-module (chickadee render viewport) + #:use-module (ice-9 match) + #:use-module (srfi srfi-9) + #:use-module (gl) + #:use-module (chickadee utils) + #:use-module (chickadee render gl) + #:use-module (chickadee render gpu) + #:use-module (chickadee color) + #:export (make-viewport + viewport? + viewport-x + viewport-y + viewport-width + viewport-height + viewport-clear-color + viewport-clear-flags + null-viewport + %standard-clear-flags + apply-viewport + *viewport-state*)) + +(define-record-type + (%make-viewport x y width height clear-color clear-flags) + viewport? + (x viewport-x) + (y viewport-y) + (width viewport-width) + (height viewport-height) + (clear-color viewport-clear-color) + (clear-flags viewport-clear-flags)) + +(define %standard-clear-flags '(color-buffer depth-buffer)) + +(define (assert-non-negative-integer n) + (if (and (integer? n) (>= n 0)) + n + (error "expecting non-negative integer:" n))) + +(define* (make-viewport x y width height #:key (clear-color black) + (clear-flags %standard-clear-flags)) + "Create a viewport that covers an area of the window starting from +coordinates (X, Y) and spanning WIDTH x HEIGHT pixels. Fill the +viewport with CLEAR-COLOR when clearing the screen. Clear the buffers +denoted by the list of symbols in CLEAR-FLAGS. Possible values for +CLEAR-FLAGS are 'color-buffer', 'depth-buffer', 'accum-buffer', and +'stencil-buffer'." + (%make-viewport (assert-non-negative-integer x) + (assert-non-negative-integer y) + (assert-non-negative-integer width) + (assert-non-negative-integer height) + clear-color + clear-flags)) + +(define null-viewport (make-viewport 0 0 0 0)) + +(define clear-buffer-mask + (memoize + (lambda (flags) + (apply logior + ;; Map symbols to OpenGL constants. + (map (match-lambda + ('depth-buffer 256) + ('accum-buffer 512) + ('stencil-buffer 1024) + ('color-buffer 16384)) + flags))))) + +(define (apply-viewport viewport) + "Set the OpenGL state for VIEWPORT. Clip rendering to the viewport +area, set the clear color, and clear necessary buffers." + (let ((x (viewport-x viewport)) + (y (viewport-y viewport)) + (w (viewport-width viewport)) + (h (viewport-height viewport)) + (c (viewport-clear-color viewport))) + (gl-enable (enable-cap scissor-test)) + (gl-viewport x y w h) + (gl-scissor x y w h) + (gl-clear-color (color-r c) (color-g c) (color-b c) (color-a c)) + (gl-clear (clear-buffer-mask (viewport-clear-flags viewport))))) + +(define *viewport-state* + (make-gpu-state apply-viewport null-viewport)) -- cgit v1.2.3