clay/bindings/odin/examples/video_demo_sdl/renderer.odin

456 lines
13 KiB
Odin

// Basic port of the C example SDL3 renderer, with a dynamic array of fonts.
package video_demo_sdl
import clay "../../clay-odin"
import "core:math"
import sdl "vendor:sdl3"
import "vendor:sdl3/ttf"
Clay_SDL3RendererData :: struct {
renderer: ^sdl.Renderer,
textEngine: ^ttf.TextEngine,
fonts: [dynamic]^ttf.Font,
}
// SDL_ttf works in pts, but clay expects pixels.
// 0.85 looks correct from what I've seen, but this calculation is probably incorrect.
px_to_pt :: proc "contextless" (pixels: f32) -> f32 {
return pixels * 0.85
}
/* Global for convenience. Even in 4K this is enough for smooth curves (low radius or rect size coupled with
* no AA or low resolution might make it appear as jagged curves) */
NUM_CIRCLE_SEGMENTS :: 16
//all rendering is performed by a single SDL call, avoiding multiple RenderRect + plumbing choice for circles.
sdl_Clay_RenderFillRoundedRect :: proc(
rendererData: ^Clay_SDL3RendererData,
rect: sdl.FRect,
cornerRadius: f32,
_color: clay.Color,
) {
color := sdl.FColor(_color / 255)
indexCount: i32 = 0
vertexCount: i32 = 0
minRadius := sdl.min(rect.w, rect.h) / 2
clampedRadius := sdl.min(cornerRadius, minRadius)
numCircleSegments := sdl.max(NUM_CIRCLE_SEGMENTS, i32(clampedRadius * 0.5))
totalVertices := 4 + (4 * (numCircleSegments * 2)) + 2 * 4
totalIndices := 6 + (4 * (numCircleSegments * 3)) + 6 * 4
// Maybe instrinsics.alloca these?
vertices := make([]sdl.Vertex, totalVertices, allocator = context.temp_allocator)
indices := make([]i32, totalIndices, allocator = context.temp_allocator)
//define center rectangle
vertices[vertexCount + 0] = (sdl.Vertex) {
{rect.x + clampedRadius, rect.y + clampedRadius},
color,
{0, 0},
} //0 center TL
vertices[vertexCount + 1] = (sdl.Vertex) {
{rect.x + rect.w - clampedRadius, rect.y + clampedRadius},
color,
{1, 0},
} //1 center TR
vertices[vertexCount + 2] = (sdl.Vertex) {
{rect.x + rect.w - clampedRadius, rect.y + rect.h - clampedRadius},
color,
{1, 1},
} //2 center BR
vertices[vertexCount + 3] = (sdl.Vertex) {
{rect.x + clampedRadius, rect.y + rect.h - clampedRadius},
color,
{0, 1},
} //3 center BL
vertexCount += 4
indices[indexCount + 0] = 0
indices[indexCount + 1] = 1
indices[indexCount + 2] = 3
indices[indexCount + 3] = 1
indices[indexCount + 4] = 2
indices[indexCount + 5] = 3
indexCount += 6
//define rounded corners as triangle fans
step := (f32(math.PI) / 2) / f32(numCircleSegments)
for i in 0 ..< numCircleSegments {
angle1 := f32(i) * step
angle2 := (f32(i) + 1) * step
for j in i32(0) ..< 4 { // Iterate over four corners
cx, cy, signX, signY: f32
switch (j) {
case 0:
cx = rect.x + clampedRadius
cy = rect.y + clampedRadius
signX = -1
signY = -1
// Top-left
case 1:
cx = rect.x + rect.w - clampedRadius
cy = rect.y + clampedRadius
signX = 1
signY = -1 // Top-right
case 2:
cx = rect.x + rect.w - clampedRadius
cy = rect.y + rect.h - clampedRadius
signX = 1
signY = 1 // Bottom-right
case 3:
cx = rect.x + clampedRadius
cy = rect.y + rect.h - clampedRadius
signX = -1
signY = 1 // Bottom-left
case:
return
}
vertices[vertexCount + 0] = (sdl.Vertex) {
{
cx + sdl.cosf(angle1) * clampedRadius * signX,
cy + sdl.sinf(angle1) * clampedRadius * signY,
},
color,
{0, 0},
}
vertices[vertexCount + 1] = (sdl.Vertex) {
{
cx + sdl.cosf(angle2) * clampedRadius * signX,
cy + sdl.sinf(angle2) * clampedRadius * signY,
},
color,
{0, 0},
}
vertexCount += 2
indices[indexCount + 0] = j // Connect to corresponding central rectangle vertex
indices[indexCount + 1] = vertexCount - 2
indices[indexCount + 2] = vertexCount - 1
indexCount += 3
}
}
//Define edge rectangles
// Top edge
vertices[vertexCount + 0] = (sdl.Vertex){{rect.x + clampedRadius, rect.y}, color, {0, 0}} //TL
vertices[vertexCount + 1] = (sdl.Vertex) {
{rect.x + rect.w - clampedRadius, rect.y},
color,
{1, 0},
} //TR
vertexCount += 2
indices[indexCount + 0] = 0
indices[indexCount + 1] = vertexCount - 2 //TL
indices[indexCount + 2] = vertexCount - 1 //TR
indices[indexCount + 3] = 1
indices[indexCount + 4] = 0
indices[indexCount + 5] = vertexCount - 1 //TR
indexCount += 6
// Right edge
vertices[vertexCount + 0] = (sdl.Vertex) {
{rect.x + rect.w, rect.y + clampedRadius},
color,
{1, 0},
} //RT
vertices[vertexCount + 1] = (sdl.Vertex) {
{rect.x + rect.w, rect.y + rect.h - clampedRadius},
color,
{1, 1},
} //RB
vertexCount += 2
indices[indexCount + 0] = 1
indices[indexCount + 1] = vertexCount - 2 //RT
indices[indexCount + 2] = vertexCount - 1 //RB
indices[indexCount + 3] = 2
indices[indexCount + 4] = 1
indices[indexCount + 5] = vertexCount - 1 //RB
indexCount += 6
// Bottom edge
vertices[vertexCount + 0] = (sdl.Vertex) {
{rect.x + rect.w - clampedRadius, rect.y + rect.h},
color,
{1, 1},
} //BR
vertices[vertexCount + 1] = (sdl.Vertex) {
{rect.x + clampedRadius, rect.y + rect.h},
color,
{0, 1},
} //BL
vertexCount += 2
indices[indexCount + 0] = 2
indices[indexCount + 1] = vertexCount - 2 //BR
indices[indexCount + 2] = vertexCount - 1 //BL
indices[indexCount + 3] = 3
indices[indexCount + 4] = 2
indices[indexCount + 5] = vertexCount - 1 //BL
indexCount += 6
// Left edge
vertices[vertexCount + 0] = (sdl.Vertex) {
{rect.x, rect.y + rect.h - clampedRadius},
color,
{0, 1},
} //LB
vertices[vertexCount + 1] = (sdl.Vertex){{rect.x, rect.y + clampedRadius}, color, {0, 0}} //LT
vertexCount += 2
indices[indexCount + 0] = 3
indices[indexCount + 1] = vertexCount - 2 //LB
indices[indexCount + 2] = vertexCount - 1 //LT
indices[indexCount + 3] = 0
indices[indexCount + 4] = 3
indices[indexCount + 5] = vertexCount - 1 //LT
indexCount += 6
// Render everything
sdl.RenderGeometry(
rendererData.renderer,
nil,
raw_data(vertices),
vertexCount,
raw_data(indices),
indexCount,
)
}
sdl_Clay_RenderArc :: proc(
rendererData: ^Clay_SDL3RendererData,
center: sdl.FPoint,
radius: f32,
startAngle: f32,
endAngle: f32,
thickness: f32,
color: clay.Color,
) {
sdl.SetRenderDrawColor(
rendererData.renderer,
u8(color.r),
u8(color.g),
u8(color.b),
u8(color.a),
)
radStart := startAngle * (math.PI / 180.0)
radEnd := endAngle * (math.PI / 180.0)
numCircleSegments := sdl.max(NUM_CIRCLE_SEGMENTS, i32(radius * 1.5)) //increase circle segments for larger circles, 1.5 is arbitrary.
angleStep := (radEnd - radStart) / f32(numCircleSegments)
thicknessStep: f32 = 0.4 //arbitrary value to avoid overlapping lines. Changing THICKNESS_STEP or numCircleSegments might cause artifacts.
for t := thicknessStep; t < thickness - thicknessStep; t += thicknessStep {
points := make([]sdl.FPoint, numCircleSegments + 1, allocator = context.temp_allocator)
clampedRadius := sdl.max(radius - t, 1)
for i in 0 ..= numCircleSegments {
angle := radStart + f32(i) * angleStep
points[i] = (sdl.FPoint) {
sdl.roundf(center.x + sdl.cosf(angle) * clampedRadius),
sdl.roundf(center.y + sdl.sinf(angle) * clampedRadius),
}
}
sdl.RenderLines(rendererData.renderer, raw_data(points), numCircleSegments + 1)
}
}
currentClippingRectangle: sdl.Rect
sdl_Clay_RenderClayCommands :: proc(
rendererData: ^Clay_SDL3RendererData,
rcommands: ^clay.ClayArray(clay.RenderCommand),
) {
for i in 0 ..< rcommands.length {
rcmd := clay.RenderCommandArray_Get(rcommands, i)
bounding_box := rcmd.boundingBox
rect := sdl.FRect{bounding_box.x, bounding_box.y, bounding_box.width, bounding_box.height}
#partial switch (rcmd.commandType) {
case .Rectangle:
config := &rcmd.renderData.rectangle
sdl.SetRenderDrawBlendMode(rendererData.renderer, sdl.BLENDMODE_BLEND)
sdl.SetRenderDrawColor(
rendererData.renderer,
u8(config.backgroundColor.r),
u8(config.backgroundColor.g),
u8(config.backgroundColor.b),
u8(config.backgroundColor.a),
)
if (config.cornerRadius.topLeft > 0) {
sdl_Clay_RenderFillRoundedRect(
rendererData,
rect,
config.cornerRadius.topLeft,
config.backgroundColor,
)
} else {
sdl.RenderFillRect(rendererData.renderer, &rect)
}
case .Text:
config := &rcmd.renderData.text
font := rendererData.fonts[config.fontId]
ttf.SetFontSize(font, px_to_pt(f32(config.fontSize)))
text := ttf.CreateText(
rendererData.textEngine,
font,
cstring(config.stringContents.chars),
uint(config.stringContents.length),
)
ttf.SetTextColor(
text,
u8(config.textColor.r),
u8(config.textColor.g),
u8(config.textColor.b),
u8(config.textColor.a),
)
ttf.DrawRendererText(text, rect.x, rect.y)
ttf.DestroyText(text)
case .Border:
config := &rcmd.renderData.border
minRadius := sdl.min(rect.w, rect.h) / 2
clampedRadii := clay.CornerRadius {
topLeft = sdl.min(config.cornerRadius.topLeft, minRadius),
topRight = sdl.min(config.cornerRadius.topRight, minRadius),
bottomLeft = sdl.min(config.cornerRadius.bottomLeft, minRadius),
bottomRight = sdl.min(config.cornerRadius.bottomRight, minRadius),
}
//edges
sdl.SetRenderDrawColor(
rendererData.renderer,
u8(config.color.r),
u8(config.color.g),
u8(config.color.b),
u8(config.color.a),
)
if (config.width.left > 0) {
starting_y := rect.y + clampedRadii.topLeft
length := rect.h - clampedRadii.topLeft - clampedRadii.bottomLeft
line := sdl.FRect{rect.x - 1, starting_y, f32(config.width.left), length}
sdl.RenderFillRect(rendererData.renderer, &line)
}
if (config.width.right > 0) {
starting_x := rect.x + rect.w - f32(config.width.right) + 1
starting_y := rect.y + clampedRadii.topRight
length := rect.h - clampedRadii.topRight - clampedRadii.bottomRight
line := sdl.FRect{starting_x, starting_y, f32(config.width.right), length}
sdl.RenderFillRect(rendererData.renderer, &line)
}
if (config.width.top > 0) {
starting_x := rect.x + clampedRadii.topLeft
length := rect.w - clampedRadii.topLeft - clampedRadii.topRight
line := sdl.FRect{starting_x, rect.y - 1, length, f32(config.width.top)}
sdl.RenderFillRect(rendererData.renderer, &line)
}
if (config.width.bottom > 0) {
starting_x := rect.x + clampedRadii.bottomLeft
starting_y := rect.y + rect.h - f32(config.width.bottom) + 1
length := rect.w - clampedRadii.bottomLeft - clampedRadii.bottomRight
line := sdl.FRect{starting_x, starting_y, length, f32(config.width.bottom)}
sdl.SetRenderDrawColor(
rendererData.renderer,
u8(config.color.r),
u8(config.color.g),
u8(config.color.b),
u8(config.color.a),
)
sdl.RenderFillRect(rendererData.renderer, &line)
}
//corners
if (config.cornerRadius.topLeft > 0) {
centerX := rect.x + clampedRadii.topLeft - 1
centerY := rect.y + clampedRadii.topLeft - 1
sdl_Clay_RenderArc(
rendererData,
(sdl.FPoint){centerX, centerY},
clampedRadii.topLeft,
180.0,
270.0,
f32(config.width.top),
config.color,
)
}
if (config.cornerRadius.topRight > 0) {
centerX := rect.x + rect.w - clampedRadii.topRight
centerY := rect.y + clampedRadii.topRight - 1
sdl_Clay_RenderArc(
rendererData,
(sdl.FPoint){centerX, centerY},
clampedRadii.topRight,
270.0,
360.0,
f32(config.width.top),
config.color,
)
}
if (config.cornerRadius.bottomLeft > 0) {
centerX := rect.x + clampedRadii.bottomLeft - 1
centerY := rect.y + rect.h - clampedRadii.bottomLeft
sdl_Clay_RenderArc(
rendererData,
(sdl.FPoint){centerX, centerY},
clampedRadii.bottomLeft,
90.0,
180.0,
f32(config.width.bottom),
config.color,
)
}
if (config.cornerRadius.bottomRight > 0) {
centerX := rect.x + rect.w - clampedRadii.bottomRight
centerY := rect.y + rect.h - clampedRadii.bottomRight
sdl_Clay_RenderArc(
rendererData,
(sdl.FPoint){centerX, centerY},
clampedRadii.bottomRight,
0.0,
90.0,
f32(config.width.bottom),
config.color,
)
}
case .ScissorStart:
boundingBox := rcmd.boundingBox
currentClippingRectangle = (sdl.Rect) {
x = i32(boundingBox.x),
y = i32(boundingBox.y),
w = i32(boundingBox.width),
h = i32(boundingBox.height),
}
sdl.SetRenderClipRect(rendererData.renderer, &currentClippingRectangle)
case .ScissorEnd:
sdl.SetRenderClipRect(rendererData.renderer, nil)
case .Image:
texture := (^sdl.Texture)(rcmd.renderData.image.imageData)
dest := sdl.FRect{rect.x, rect.y, rect.w, rect.h}
sdl.RenderTexture(rendererData.renderer, texture, nil, &dest)
case:
sdl.Log("Unknown render command type: %d", rcmd.commandType)
}
}
}